diff --git a/moto/ec2/exceptions.py b/moto/ec2/exceptions.py
index 358c84b2b..d97bc00a7 100644
--- a/moto/ec2/exceptions.py
+++ b/moto/ec2/exceptions.py
@@ -72,6 +72,14 @@ class InvalidSubnetIdError(EC2ClientError):
             .format(subnet_id))
 
 
+class InvalidNetworkInterfaceIdError(EC2ClientError):
+    def __init__(self, eni_id):
+        super(InvalidNetworkInterfaceIdError, self).__init__(
+            "InvalidNetworkInterfaceID.NotFound",
+            "The network interface ID '{0}' does not exist"
+            .format(eni_id))
+
+
 class InvalidSecurityGroupDuplicateError(EC2ClientError):
     def __init__(self, name):
         super(InvalidSecurityGroupDuplicateError, self).__init__(
diff --git a/moto/ec2/models.py b/moto/ec2/models.py
index bab604890..5245fb098 100644
--- a/moto/ec2/models.py
+++ b/moto/ec2/models.py
@@ -26,6 +26,7 @@ from .exceptions import (
     ResourceAlreadyAssociatedError,
     InvalidVPCIdError,
     InvalidSubnetIdError,
+    InvalidNetworkInterfaceIdError,
     InvalidSecurityGroupDuplicateError,
     InvalidSecurityGroupNotFoundError,
     InvalidPermissionNotFoundError,
@@ -48,11 +49,14 @@ from .utils import (
     random_dhcp_option_id,
     random_eip_allocation_id,
     random_eip_association_id,
+    random_eni_attach_id,
+    random_eni_id,
     random_internet_gateway_id,
     random_instance_id,
     random_internet_gateway_id,
     random_ip,
     random_key_pair,
+    random_public_ip,
     random_reservation_id,
     random_route_table_id,
     random_security_group_id,
@@ -77,6 +81,172 @@ class TaggedEC2Instance(object):
         return tags
 
 
+class NetworkInterface(object):
+    def __init__(self, subnet, private_ip_address, device_index=0, public_ip_auto_assign=True, group_ids=None):
+        self.id = random_eni_id()
+        self.device_index = device_index
+        self.private_ip_address = private_ip_address
+        self.subnet = subnet
+        self.instance = None
+
+        self.public_ip = None
+        self.public_ip_auto_assign = public_ip_auto_assign
+        self.start()
+
+        self.attachments = []
+        self.group_set = []
+
+        group = None
+        if group_ids:
+            for group_id in group_ids:
+                group = ec2_backend.get_security_group_from_id(group_id)
+                if not group:
+                    # Create with specific group ID.
+                    group = SecurityGroup(group_id, group_id, group_id, vpc_id=subnet.vpc_id)
+                    ec2_backend.groups[subnet.vpc_id][group_id] = group
+                if group:
+                    self.group_set.append(group)
+
+    @classmethod
+    def create_from_cloudformation_json(cls, resource_name, cloudformation_json):
+        properties = cloudformation_json['Properties']
+
+        security_group_ids = properties.get('SecurityGroups', [])
+
+        subnet_id = properties['SubnetId']
+        subnet = ec2_backend.get_subnet(subnet_id)
+
+        private_ip_address = properties.get('PrivateIpAddress', None)
+
+        network_interface = ec2_backend.create_network_interface(
+            subnet,
+            private_ip_address,
+            group_ids=security_group_ids
+        )
+        return network_interface
+
+    def stop(self):
+        if self.public_ip_auto_assign:
+            self.public_ip = None
+
+    def start(self):
+        self.check_auto_public_ip()
+
+    def check_auto_public_ip(self):
+        if self.public_ip_auto_assign:
+            self.public_ip = random_public_ip()
+
+    def attach(self, instance_id, device_index):
+        attachment = {'attachmentId': random_eni_attach_id(),
+                      'instanceId': instance_id,
+                      'deviceIndex': device_index}
+        self.attachments.append(attachment)
+
+
+class NetworkInterfaceBackend(object):
+    def __init__(self):
+        self.enis = {}
+        super(NetworkInterfaceBackend, self).__init__()
+
+    def create_network_interface(self, subnet, private_ip_address, group_ids=None, **kwargs):
+        eni = NetworkInterface(subnet, private_ip_address, group_ids=group_ids)
+        self.enis[eni.id] = eni
+        return eni
+
+    def get_network_interface(self, eni_id):
+        for eni in self.enis.values():
+            if eni_id == eni.id:
+                return eni
+        raise InvalidNetworkInterfaceIdError(eni_id)
+
+    def delete_network_interface(self, eni_id):
+        deleted = self.enis.pop(eni_id, None)
+        if not deleted:
+            raise InvalidNetworkInterfaceIdError(eni_id)
+        return deleted
+
+    def describe_network_interfaces(self, filters=None):
+        enis = self.enis.values()
+
+        if filters:
+            for (_filter, _filter_value) in filters.items():
+                if _filter == 'network-interface-id':
+                    _filter = 'id'
+                    enis = [ eni for eni in enis if getattr(eni, _filter) in _filter_value ]
+                elif _filter == 'group-id':
+                    original_enis = enis
+                    enis = []
+                    for eni in original_enis:
+                        group_ids = []
+                        for group in eni.group_set:
+                            if group.id in _filter_value:
+                                enis.append(eni)
+                                break
+                else:
+                    ec2_backend.raise_not_implemented_error("The filter '{0}' for DescribeNetworkInterfaces".format(_filter))
+        return enis
+
+    def modify_network_interface_attribute(self, eni_id, group_id):
+        eni = self.get_network_interface(eni_id)
+        group = self.get_security_group_from_id(group_id)
+        eni.group_set = [group]
+
+    def prep_nics_for_instance(self, instance, nic_spec, subnet_id=None, private_ip=None, associate_public_ip=None):
+        nics = {}
+
+        # Primary NIC defaults
+        primary_nic = {'SubnetId': subnet_id,
+                       'PrivateIpAddress': private_ip,
+                       'AssociatePublicIpAddress': associate_public_ip}
+        primary_nic = dict((k,v) for k, v in primary_nic.items() if v)
+
+        # If empty NIC spec but primary NIC values provided, create NIC from them.
+        if primary_nic and not nic_spec:
+            nic_spec[0] = primary_nic
+            nic_spec[0]['DeviceIndex'] = 0
+
+        # Flesh out data structures and associations
+        for nic in nic_spec.values():
+            use_eni = None
+            security_group_ids = []
+
+            device_index = int(nic.get('DeviceIndex'))
+
+            nic_id = nic.get('NetworkInterfaceId', None)
+            if nic_id:
+                # If existing NIC found, use it.
+                use_nic = ec2_backend.get_network_interface(nic_id)
+                use_nic.device_index = device_index
+                use_nic.public_ip_auto_assign = False
+
+            else:
+                # If primary NIC values provided, use them for the primary NIC.
+                if device_index == 0 and primary_nic:
+                    nic.update(primary_nic)
+
+                subnet = ec2_backend.get_subnet(nic['SubnetId'])
+
+                group_id = nic.get('SecurityGroupId',None)
+                group_ids = [group_id] if group_id else []
+
+                use_nic = ec2_backend.create_network_interface(subnet,
+                                                               nic.get('PrivateIpAddress',None),
+                                                               device_index=device_index,
+                                                               public_ip_auto_assign=nic.get('AssociatePublicIpAddress',False),
+                                                               group_ids=group_ids)
+
+            use_nic.instance = instance # This is used upon associate/disassociate public IP.
+
+            if use_nic.instance.security_groups:
+                use_nic.group_set.extend(use_nic.instance.security_groups)
+
+            use_nic.attach(instance.id, device_index)
+
+            nics[device_index] = use_nic
+
+        return nics
+
+
 class Instance(BotoInstance, TaggedEC2Instance):
     def __init__(self, image_id, user_data, security_groups, **kwargs):
         super(Instance, self).__init__()
@@ -108,6 +278,12 @@ class Instance(BotoInstance, TaggedEC2Instance):
                 # string will have a "u" prefix -- need to get rid of it
                 self.user_data[0] = self.user_data[0].encode('utf-8')
 
+        self.nics = ec2_backend.prep_nics_for_instance(self,
+                                                       kwargs.get("nics", {}),
+                                                       subnet_id=kwargs.get("subnet_id",None),
+                                                       private_ip=kwargs.get("private_ip",None),
+                                                       associate_public_ip=kwargs.get("associate_public_ip",None))
+
     @classmethod
     def create_from_cloudformation_json(cls, resource_name, cloudformation_json):
         properties = cloudformation_json['Properties']
@@ -131,14 +307,23 @@ class Instance(BotoInstance, TaggedEC2Instance):
         return self.id
 
     def start(self, *args, **kwargs):
+        for nic in self.nics.values():
+            nic.start()
+
         self._state.name = "running"
         self._state.code = 16
 
     def stop(self, *args, **kwargs):
+        for nic in self.nics.values():
+            nic.stop()
+
         self._state.name = "stopped"
         self._state.code = 80
 
     def terminate(self, *args, **kwargs):
+        for nic in self.nics.values():
+            nic.stop()
+
         self._state.name = "terminated"
         self._state.code = 48
 
@@ -146,6 +331,21 @@ class Instance(BotoInstance, TaggedEC2Instance):
         self._state.name = "running"
         self._state.code = 16
 
+    def get_tags(self):
+        tags = ec2_backend.describe_tags(self.id)
+        return tags
+
+    @property
+    def dynamic_group_list(self):
+        if self.nics:
+            groups = []
+            for nic in self.nics.values():
+                for group in nic.group_set:
+                    groups.append(group)
+            return groups
+        else:
+            return self.security_groups
+
 
 class InstanceBackend(object):
 
@@ -511,6 +711,7 @@ class SecurityGroup(object):
         self.description = description
         self.ingress_rules = []
         self.egress_rules = []
+        self.enis = {}
         self.vpc_id = vpc_id
 
     @classmethod
@@ -569,18 +770,23 @@ class SecurityGroupBackend(object):
     def describe_security_groups(self):
         return itertools.chain(*[x.values() for x in self.groups.values()])
 
+    def _delete_security_group(self, vpc_id, group_id):
+        if self.groups[vpc_id][group_id].enis:
+            raise DependencyViolationError("{0} is being utilized by {1}".format(group_id, 'ENIs'))
+        return self.groups[vpc_id].pop(group_id)
+
     def delete_security_group(self, name=None, group_id=None):
         if group_id:
             # loop over all the SGs, find the right one
-            for vpc in self.groups.values():
-                if group_id in vpc:
-                    return vpc.pop(group_id)
+            for vpc_id, groups in self.groups.items():
+                if group_id in groups:
+                    return self._delete_security_group(vpc_id, group_id)
             raise InvalidSecurityGroupNotFoundError(group_id)
         elif name:
             # Group Name.  Has to be in standard EC2, VPC needs to be identified by group_id
             group = self.get_security_group_from_name(name)
             if group:
-                return self.groups[None].pop(group.id)
+                return self._delete_security_group(None, group.id)
             raise InvalidSecurityGroupNotFoundError(name)
 
     def get_security_group_from_id(self, group_id):
@@ -1003,6 +1209,12 @@ class SubnetBackend(object):
         self.subnets = {}
         super(SubnetBackend, self).__init__()
 
+    def get_subnet(self, subnet_id):
+        subnet = self.subnets.get(subnet_id, None)
+        if not subnet:
+            raise InvalidSubnetIdError(subnet_id)
+        return subnet
+
     def create_subnet(self, vpc_id, cidr_block):
         subnet_id = random_subnet_id()
         subnet = Subnet(subnet_id, vpc_id, cidr_block)
@@ -1289,6 +1501,7 @@ class ElasticAddress(object):
         self.allocation_id = random_eip_allocation_id() if domain == "vpc" else None
         self.domain = domain
         self.instance = None
+        self.eni = None
         self.association_id = None
 
     @classmethod
@@ -1355,7 +1568,7 @@ class ElasticAddressBackend(object):
 
         return eips
 
-    def associate_address(self, instance, address=None, allocation_id=None, reassociate=False):
+    def associate_address(self, instance=None, eni=None, address=None, allocation_id=None, reassociate=False):
         eips = []
         if address:
             eips = self.address_by_ip([address])
@@ -1363,13 +1576,20 @@ class ElasticAddressBackend(object):
             eips = self.address_by_allocation([allocation_id])
         eip = eips[0]
 
-        if eip.instance and not reassociate:
-            raise ResourceAlreadyAssociatedError(eip.public_ip)
+        new_instance_association = bool(instance and (not eip.instance or eip.instance.id == instance.id))
+        new_eni_association = bool(eni and (not eip.eni or eni.id == eip.eni.id))
 
-        eip.instance = instance
-        if eip.domain == "vpc":
-            eip.association_id = random_eip_association_id()
-        return eip
+        if new_instance_association or new_eni_association or reassociate:
+            eip.instance = instance
+            eip.eni = eni
+            if eip.eni:
+                eip.eni.public_ip = eip.public_ip
+            if eip.domain == "vpc":
+                eip.association_id = random_eip_association_id()
+
+            return eip
+
+        raise ResourceAlreadyAssociatedError(eip.public_ip)
 
     def describe_addresses(self):
         return self.addresses
@@ -1382,6 +1602,13 @@ class ElasticAddressBackend(object):
             eips = self.address_by_association([association_id])
         eip = eips[0]
 
+        if eip.eni:
+            if eip.eni.instance and eip.eni.instance._state.name == "running":
+                eip.eni.check_auto_public_ip()
+            else:
+                eip.eni.public_ip = None
+            eip.eni = None
+
         eip.instance = None
         eip.association_id = None
         return True
@@ -1474,6 +1701,7 @@ class DHCPOptionsSetBackend(object):
 class EC2Backend(BaseBackend, InstanceBackend, TagBackend, AmiBackend,
                  RegionsAndZonesBackend, SecurityGroupBackend, EBSBackend,
                  VPCBackend, SubnetBackend, SubnetRouteTableAssociationBackend,
+                 NetworkInterfaceBackend,
                  VPCPeeringConnectionBackend,
                  RouteTableBackend, RouteBackend, InternetGatewayBackend,
                  VPCGatewayAttachmentBackend, SpotRequestBackend,
diff --git a/moto/ec2/responses/elastic_ip_addresses.py b/moto/ec2/responses/elastic_ip_addresses.py
index 7169eb854..ff7e77be3 100644
--- a/moto/ec2/responses/elastic_ip_addresses.py
+++ b/moto/ec2/responses/elastic_ip_addresses.py
@@ -17,10 +17,12 @@ class ElasticIPAddresses(BaseResponse):
         return template.render(address=address)
 
     def associate_address(self):
+        instance = eni = None
+
         if "InstanceId" in self.querystring:
             instance = ec2_backend.get_instance(self.querystring['InstanceId'][0])
         elif "NetworkInterfaceId" in self.querystring:
-            raise NotImplementedError("Lookup by allocation id not implemented")
+            eni = ec2_backend.get_network_interface(self.querystring['NetworkInterfaceId'][0])
         else:
             ec2_backend.raise_error("MissingParameter", "Invalid request, expect InstanceId/NetworkId parameter.")
 
@@ -28,12 +30,15 @@ class ElasticIPAddresses(BaseResponse):
         if "AllowReassociation" in self.querystring:
             reassociate = self.querystring['AllowReassociation'][0] == "true"
 
-        if "PublicIp" in self.querystring:
-            eip = ec2_backend.associate_address(instance, address=self.querystring['PublicIp'][0], reassociate=reassociate)
-        elif "AllocationId" in self.querystring:
-            eip = ec2_backend.associate_address(instance, allocation_id=self.querystring['AllocationId'][0], reassociate=reassociate)
+        if instance or eni:
+            if "PublicIp" in self.querystring:
+                eip = ec2_backend.associate_address(instance=instance, eni=eni, address=self.querystring['PublicIp'][0], reassociate=reassociate)
+            elif "AllocationId" in self.querystring:
+                eip = ec2_backend.associate_address(instance=instance, eni=eni, allocation_id=self.querystring['AllocationId'][0], reassociate=reassociate)
+            else:
+                ec2_backend.raise_error("MissingParameter", "Invalid request, expect PublicIp/AllocationId parameter.")
         else:
-            ec2_backend.raise_error("MissingParameter", "Invalid request, expect PublicIp/AllocationId parameter.")
+            ec2_backend.raise_error("MissingParameter", "Invalid request, expect either instance or ENI.")
 
         template = Template(ASSOCIATE_ADDRESS_RESPONSE)
         return template.render(address=eip)
@@ -103,6 +108,11 @@ DESCRIBE_ADDRESS_RESPONSE = """<DescribeAddressesResponse xmlns="http://ec2.amaz
           {% else %}
             <instanceId/>
           {% endif %}
+          {% if address.eni %}
+            <networkInterfaceId>{{ address.eni.id }}</networkInterfaceId>
+          {% else %}
+            <networkInterfaceId/>
+          {% endif %}
           {% if address.allocation_id %}
             <allocationId>{{ address.allocation_id }}</allocationId>
           {% endif %}
diff --git a/moto/ec2/responses/elastic_network_interfaces.py b/moto/ec2/responses/elastic_network_interfaces.py
index 596b2be9f..c6d167946 100644
--- a/moto/ec2/responses/elastic_network_interfaces.py
+++ b/moto/ec2/responses/elastic_network_interfaces.py
@@ -1,5 +1,9 @@
 from __future__ import unicode_literals
+from jinja2 import Template
+
 from moto.core.responses import BaseResponse
+from moto.ec2.models import ec2_backend
+from moto.ec2.utils import sequence_from_querystring, resource_ids_from_querystring, filters_from_querystring
 
 
 class ElasticNetworkInterfaces(BaseResponse):
@@ -7,22 +11,157 @@ class ElasticNetworkInterfaces(BaseResponse):
         raise NotImplementedError('ElasticNetworkInterfaces(AmazonVPC).attach_network_interface is not yet implemented')
 
     def create_network_interface(self):
-        raise NotImplementedError('ElasticNetworkInterfaces(AmazonVPC).create_network_interface is not yet implemented')
+        subnet_id = self.querystring.get('SubnetId')[0]
+        private_ip_address = self.querystring.get('PrivateIpAddress', [None])[0]
+        groups = sequence_from_querystring('SecurityGroupId', self.querystring)
+        subnet = ec2_backend.get_subnet(subnet_id)
+        eni = ec2_backend.create_network_interface(subnet, private_ip_address, groups)
+        template = Template(CREATE_NETWORK_INTERFACE_RESPONSE)
+        return template.render(eni=eni)
 
     def delete_network_interface(self):
-        raise NotImplementedError('ElasticNetworkInterfaces(AmazonVPC).delete_network_interface is not yet implemented')
+        eni_id = self.querystring.get('NetworkInterfaceId')[0]
+        eni = ec2_backend.delete_network_interface(eni_id)
+        template = Template(DELETE_NETWORK_INTERFACE_RESPONSE)
+        return template.render()
 
     def describe_network_interface_attribute(self):
         raise NotImplementedError('ElasticNetworkInterfaces(AmazonVPC).describe_network_interface_attribute is not yet implemented')
 
     def describe_network_interfaces(self):
-        raise NotImplementedError('ElasticNetworkInterfaces(AmazonVPC).describe_network_interfaces is not yet implemented')
+        #Partially implemented. Supports only network-interface-id and group-id filters
+        filters = filters_from_querystring(self.querystring)
+        enis = ec2_backend.describe_network_interfaces(filters)
+        template = Template(DESCRIBE_NETWORK_INTERFACES_RESPONSE)
+        return template.render(enis=enis)
 
     def detach_network_interface(self):
         raise NotImplementedError('ElasticNetworkInterfaces(AmazonVPC).detach_network_interface is not yet implemented')
 
     def modify_network_interface_attribute(self):
-        raise NotImplementedError('ElasticNetworkInterfaces(AmazonVPC).modify_network_interface_attribute is not yet implemented')
+        #Currently supports modifying one and only one security group
+        eni_id = self.querystring.get('NetworkInterfaceId')[0]
+        group_id = self.querystring.get('SecurityGroupId.1')[0]
+        ec2_backend.modify_network_interface_attribute(eni_id, group_id)
+        return MODIFY_NETWORK_INTERFACE_ATTRIBUTE_RESPONSE
 
     def reset_network_interface_attribute(self):
         raise NotImplementedError('ElasticNetworkInterfaces(AmazonVPC).reset_network_interface_attribute is not yet implemented')
+
+CREATE_NETWORK_INTERFACE_RESPONSE = """
+<CreateNetworkInterfaceResponse xmlns="http://ec2.amazonaws.com/doc/2013-07-15/">
+    <requestId>2c6021ec-d705-445a-9780-420d0c7ab793</requestId>
+    <networkInterface>
+        <networkInterfaceId>{{ eni.id }}</networkInterfaceId>
+        <subnetId>{{ eni.subnet.id }}</subnetId>
+        <vpcId>{{ eni.subnet.vpc_id }}</vpcId>
+        <availabilityZone>us-west-2a</availabilityZone>
+        <description/>
+        <ownerId>498654062920</ownerId>
+        <requesterManaged>false</requesterManaged>
+        <status>pending</status>
+        <macAddress>02:07:a9:b6:12:51</macAddress>
+        {% if eni.private_ip_address %}
+          <privateIpAddress>{{ eni.private_ip_address }}</privateIpAddress>
+        {% endif %}
+        <sourceDestCheck>true</sourceDestCheck>
+        <groupSet>
+        {% for group in eni.group_set %}
+            <item>
+                <groupId>{{ group.id }}</groupId>
+                <groupName>{{ group.name }}</groupName>
+             </item>
+         {% endfor %}
+         </groupSet>
+        <tagSet/>
+        {% if eni.private_ip_address %}
+          <privateIpAddressesSet>
+              <item>
+                  <privateIpAddress>{{ eni.private_ip_address }}</privateIpAddress>
+                  <primary>true</primary>
+              </item>
+          </privateIpAddressesSet>
+        {% else %}
+          <privateIpAddressesSet/>
+        {% endif %}
+    </networkInterface>
+</CreateNetworkInterfaceResponse>
+"""
+
+DESCRIBE_NETWORK_INTERFACES_RESPONSE = """<DescribeNetworkInterfacesResponse xmlns="http://ec2.amazonaws.com/doc/2013-07-15/">
+    <requestId>ddb0aaf1-8b65-4f0a-94fa-654b18b8a204</requestId>
+    <networkInterfaceSet>
+    {% for eni in enis %}
+        <item>
+           <networkInterfaceId>{{ eni.id }}</networkInterfaceId>
+           <subnetId>{{ eni.subnet.id }}</subnetId>
+           <vpcId>vpc-9367a6f8</vpcId>
+           <availabilityZone>us-west-2a</availabilityZone>
+           <description>Primary network interface</description>
+           <ownerId>190610284047</ownerId>
+           <requesterManaged>false</requesterManaged>
+           <status>in-use</status>
+           <macAddress>0e:a3:a7:7b:95:a7</macAddress>
+           {% if eni.private_ip_address %}
+             <privateIpAddress>{{ eni.private_ip_address }}</privateIpAddress>
+           {% endif %}
+           <privateDnsName>ip-10-0-0-134.us-west-2.compute.internal</privateDnsName>
+           <sourceDestCheck>true</sourceDestCheck>
+           <groupSet>
+           {% for group in eni.group_set %}
+               <item>
+                   <groupId>{{ group.id }}</groupId>
+                   <groupName>{{ group.name }}</groupName>
+                </item>
+            {% endfor %}
+            </groupSet>
+            {% for attachment in eni.attachments %}
+            <attachment>
+                <attachmentId>{{ attachment['attachmentId'] }}</attachmentId>
+                <instanceId>{{ attachment['instanceId'] }}</instanceId>
+                <instanceOwnerId>190610284047</instanceOwnerId>
+                <deviceIndex>{{ attachment['deviceIndex'] }}</deviceIndex>
+                <status>attached</status>
+                <attachTime>2013-10-04T17:38:53.000Z</attachTime>
+                <deleteOnTermination>true</deleteOnTermination>
+            </attachment>
+            {% endfor %}
+            <association>
+                <publicIp>{{ eni.public_ip }}</publicIp>
+                <publicDnsName>ec2-54-200-86-47.us-west-2.compute.amazonaws.com</publicDnsName>
+                <ipOwnerId>amazon</ipOwnerId>
+            </association>
+            <tagSet/>
+            {% if eni.private_ip_address %}
+              <privateIpAddressesSet>
+                  <item>
+                      <privateIpAddress>{{ eni.private_ip_address }}</privateIpAddress>
+                      <privateDnsName>ip-10-0-0-134.us-west-2.compute.internal</privateDnsName>
+                      <primary>true</primary>
+                      {% if eni.public_ip %}
+                        <association>
+                            <publicIp>{{ eni.public_ip }}</publicIp>
+                            <publicDnsName>ec2-54-200-86-47.us-west-2.compute.amazonaws.com</publicDnsName>
+                            <ipOwnerId>amazon</ipOwnerId>
+                        </association>
+                      {% endif %}
+                  </item>
+              </privateIpAddressesSet>
+            {% else %}
+              <privateIpAddressesSet/>
+            {% endif %}
+        </item>
+    {% endfor %}
+    </networkInterfaceSet>
+</DescribeNetworkInterfacesResponse>"""
+
+MODIFY_NETWORK_INTERFACE_ATTRIBUTE_RESPONSE = """<ModifyNetworkInterfaceAttributeResponse xmlns="http://ec2.amazonaws.com/doc/2012-12-01/">
+  <requestId>59dbff89-35bd-4eac-99ed-be587EXAMPLE</requestId>
+  <return>true</return>
+</ModifyNetworkInterfaceAttributeResponse>"""
+
+DELETE_NETWORK_INTERFACE_RESPONSE = """
+<DeleteNetworkInterfaceResponse xmlns="http://ec2.amazonaws.com/doc/2013-07-15/">
+    <requestId>34b5b3b4-d0c5-49b9-b5e2-a468ef6adcd8</requestId>
+    <return>true</return>
+</DeleteNetworkInterfaceResponse>"""
diff --git a/moto/ec2/responses/instances.py b/moto/ec2/responses/instances.py
index 863fe6600..c92de014b 100644
--- a/moto/ec2/responses/instances.py
+++ b/moto/ec2/responses/instances.py
@@ -3,7 +3,7 @@ from jinja2 import Template
 
 from moto.core.responses import BaseResponse
 from moto.core.utils import camelcase_to_underscores
-from moto.ec2.utils import instance_ids_from_querystring, filters_from_querystring, filter_reservations
+from moto.ec2.utils import instance_ids_from_querystring, filters_from_querystring, filter_reservations, dict_from_querystring
 
 
 class InstanceResponse(BaseResponse):
@@ -26,13 +26,19 @@ class InstanceResponse(BaseResponse):
         user_data = self.querystring.get('UserData')
         security_group_names = self._get_multi_param('SecurityGroup')
         security_group_ids = self._get_multi_param('SecurityGroupId')
+        nics = dict_from_querystring("NetworkInterface", self.querystring)
         instance_type = self.querystring.get("InstanceType", ["m1.small"])[0]
         subnet_id = self.querystring.get("SubnetId", [None])[0]
+        private_ip = self.querystring.get("PrivateIpAddress", [None])[0]
+        associate_public_ip = self.querystring.get("AssociatePublicIpAddress", [None])[0]
         key_name = self.querystring.get("KeyName", [None])[0]
+
         new_reservation = self.ec2_backend.add_instances(
             image_id, min_count, user_data, security_group_names,
             instance_type=instance_type, subnet_id=subnet_id,
-            key_name=key_name, security_group_ids=security_group_ids)
+            key_name=key_name, security_group_ids=security_group_ids,
+            nics=nics, private_ip=private_ip, associate_public_ip=associate_public_ip)
+
         template = Template(EC2_RUN_INSTANCES)
         return template.render(reservation=new_reservation)
 
@@ -189,10 +195,19 @@ EC2_RUN_INSTANCES = """<RunInstancesResponse xmlns="http://ec2.amazonaws.com/doc
           <monitoring>
             <state>enabled</state>
           </monitoring>
-          <subnetId>{{ instance.subnet_id }}</subnetId>
+          {% if instance.nics %}
+            <subnetId>{{ instance.nics[0].subnet.id }}</subnetId>
+            <vpcId>{{ instance.nics[0].subnet.vpc_id }}</vpcId>
+            <privateIpAddress>{{ instance.nics[0].private_ip_address }}</privateIpAddress>
+            {% if instance.nics[0].public_ip %}
+            <ipAddress>46.51.219.63</ipAddress>
+            {% endif %}
+          {% else %}
+            <subnetId>{{ instance.subnet_id }}</subnetId>
+          {% endif %}
           <sourceDestCheck>true</sourceDestCheck>
           <groupSet>
-             {% for group in instance.security_groups %}
+             {% for group in instance.dynamic_group_list %}
              <item>
                 <groupId>{{ group.id }}</groupId>
                 <groupName>{{ group.name }}</groupName>
@@ -208,6 +223,54 @@ EC2_RUN_INSTANCES = """<RunInstancesResponse xmlns="http://ec2.amazonaws.com/doc
           <clientToken/>
           <hypervisor>xen</hypervisor>
           <ebsOptimized>false</ebsOptimized>
+          <networkInterfaceSet>
+            {% for nic in instance.nics.values() %}
+              <item>
+                <networkInterfaceId>{{ nic.id }}</networkInterfaceId>
+                <subnetId>{{ nic.subnet.id }}</subnetId>
+                <vpcId>{{ nic.subnet.vpc_id }}</vpcId>
+                <description>Primary network interface</description>
+                <ownerId>111122223333</ownerId>
+                <status>in-use</status>
+                <macAddress>1b:2b:3c:4d:5e:6f</macAddress>
+                <privateIpAddress>{{ nic.private_ip_address }}</privateIpAddress>
+                <sourceDestCheck>true</sourceDestCheck>
+                <groupSet>
+                  {% for group in nic.group_set %}
+                  <item>
+                    <groupId>{{ group.id }}</groupId>
+                    <groupName>{{ group.name }}</groupName>
+                  </item>
+                  {% endfor %}
+                </groupSet>
+                <attachment>
+                  <attachmentId>eni-attach-1a2b3c4d</attachmentId>
+                  <deviceIndex>{{ nic.device_index }}</deviceIndex>
+                  <status>attached</status>
+                  <attachTime>YYYY-MM-DDTHH:MM:SS+0000</attachTime>
+                  <deleteOnTermination>true</deleteOnTermination>
+                </attachment>
+                {% if nic.public_ip %}
+                  <association>
+                    <publicIp>{{ nic.public_ip }}</publicIp>
+                    <ipOwnerId>111122223333</ipOwnerId>
+                  </association>
+                {% endif %}
+                <privateIpAddressesSet>
+                  <item>
+                    <privateIpAddress>{{ nic.private_ip_address }}</privateIpAddress>
+                    <primary>true</primary>
+                    {% if nic.public_ip %}
+                      <association>
+                        <publicIp>{{ nic.public_ip }}</publicIp>
+                        <ipOwnerId>111122223333</ipOwnerId>
+                      </association>
+                    {% endif %}
+                  </item>
+                </privateIpAddressesSet>
+              </item>
+            {% endfor %}
+          </networkInterfaceSet>
         </item>
     {% endfor %}
   </instancesSet>
@@ -220,7 +283,14 @@ EC2_DESCRIBE_INSTANCES = """<DescribeInstancesResponse xmlns='http://ec2.amazona
           <item>
             <reservationId>{{ reservation.id }}</reservationId>
             <ownerId>111122223333</ownerId>
-            <groupSet></groupSet>
+            <groupSet>
+              {% for group in reservation.dynamic_group_list %}
+              <item>
+                <groupId>{{ group.id }}</groupId>
+                <groupName>{{ group.name }}</groupName>
+              </item>
+              {% endfor %}
+            </groupSet>
             <instancesSet>
                 {% for instance in reservation.instances %}
                   <item>
@@ -249,13 +319,17 @@ EC2_DESCRIBE_INSTANCES = """<DescribeInstancesResponse xmlns='http://ec2.amazona
                     <monitoring>
                       <state>disabled</state>
                     </monitoring>
-                    <subnetId>{{ instance.subnet_id }}</subnetId>
-                    <vpcId>vpc-1a2b3c4d</vpcId>
-                    <privateIpAddress>10.0.0.12</privateIpAddress>
-                    <ipAddress>46.51.219.63</ipAddress>
+                    {% if instance.nics %}
+                      <subnetId>{{ instance.nics[0].subnet.id }}</subnetId>
+                      <vpcId>{{ instance.nics[0].subnet.vpc_id }}</vpcId>
+                      <privateIpAddress>{{ instance.nics[0].private_ip_address }}</privateIpAddress>
+                      {% if instance.nics[0].public_ip %}
+                      <ipAddress>46.51.219.63</ipAddress>
+                      {% endif %}
+                    {% endif %}
                     <sourceDestCheck>true</sourceDestCheck>
                     <groupSet>
-                      {% for group in instance.security_groups %}
+                      {% for group in instance.dynamic_group_list %}
                       <item>
                         <groupId>{{ group.id }}</groupId>
                         <groupName>{{ group.name }}</groupName>
@@ -280,7 +354,54 @@ EC2_DESCRIBE_INSTANCES = """<DescribeInstancesResponse xmlns='http://ec2.amazona
                       {% endfor %}
                     </tagSet>
                     <hypervisor>xen</hypervisor>
-                    <networkInterfaceSet />
+                    <networkInterfaceSet>
+                      {% for nic in instance.nics.values() %}
+                        <item>
+                          <networkInterfaceId>{{ nic.id }}</networkInterfaceId>
+                          <subnetId>{{ nic.subnet.id }}</subnetId>
+                          <vpcId>{{ nic.subnet.vpc_id }}</vpcId>
+                          <description>Primary network interface</description>
+                          <ownerId>111122223333</ownerId>
+                          <status>in-use</status>
+                          <macAddress>1b:2b:3c:4d:5e:6f</macAddress>
+                          <privateIpAddress>{{ nic.private_ip_address }}</privateIpAddress>
+                          <sourceDestCheck>true</sourceDestCheck>
+                          <groupSet>
+                            {% for group in nic.group_set %}
+                            <item>
+                              <groupId>{{ group.id }}</groupId>
+                              <groupName>{{ group.name }}</groupName>
+                            </item>
+                            {% endfor %}
+                          </groupSet>
+                          <attachment>
+                            <attachmentId>eni-attach-1a2b3c4d</attachmentId>
+                            <deviceIndex>{{ nic.device_index }}</deviceIndex>
+                            <status>attached</status>
+                            <attachTime>YYYY-MM-DDTHH:MM:SS+0000</attachTime>
+                            <deleteOnTermination>true</deleteOnTermination>
+                          </attachment>
+                          {% if nic.public_ip %}
+                            <association>
+                              <publicIp>{{ nic.public_ip }}</publicIp>
+                              <ipOwnerId>111122223333</ipOwnerId>
+                            </association>
+                          {% endif %}
+                          <privateIpAddressesSet>
+                            <item>
+                              <privateIpAddress>{{ nic.private_ip_address }}</privateIpAddress>
+                              <primary>true</primary>
+                              {% if nic.public_ip %}
+                                <association>
+                                  <publicIp>{{ nic.public_ip }}</publicIp>
+                                  <ipOwnerId>111122223333</ipOwnerId>
+                                </association>
+                              {% endif %}
+                            </item>
+                          </privateIpAddressesSet>
+                        </item>
+                      {% endfor %}
+                    </networkInterfaceSet>
                   </item>
                 {% endfor %}
             </instancesSet>
diff --git a/moto/ec2/utils.py b/moto/ec2/utils.py
index 667d97f28..d8646c8a0 100644
--- a/moto/ec2/utils.py
+++ b/moto/ec2/utils.py
@@ -72,6 +72,18 @@ def random_dhcp_option_id():
     return random_id(prefix='dopt')
 
 
+def random_eni_id():
+    return random_id(prefix='eni')
+
+
+def random_eni_attach_id():
+    return random_id(prefix='eni-attach')
+
+
+def random_public_ip():
+    return '54.214.{0}.{1}'.format(random.choice(range(255)),
+                                   random.choice(range(255)))
+
 def random_ip():
     return "127.{0}.{1}.{2}".format(
         random.randint(0, 255),
@@ -172,6 +184,21 @@ def filters_from_querystring(querystring_dict):
     return response_values
 
 
+def dict_from_querystring(parameter, querystring_dict):
+    use_dict={}
+    for key, value in querystring_dict.items():
+        match = re.search(r"{0}.(\d).(\w+)".format(parameter), key)
+        if match:
+            use_dict_index = match.groups()[0]
+            use_dict_element_property = match.groups()[1]
+
+            if not use_dict.get(use_dict_index):
+                use_dict[use_dict_index] = {}
+            use_dict[use_dict_index][use_dict_element_property]=value[0]
+
+    return use_dict
+
+
 def keypair_names_from_querystring(querystring_dict):
     keypair_names = []
     for key, value in querystring_dict.items():
diff --git a/tests/test_ec2/test_elastic_ip_addresses.py b/tests/test_ec2/test_elastic_ip_addresses.py
index fe0e57e58..f32c2e59c 100644
--- a/tests/test_ec2/test_elastic_ip_addresses.py
+++ b/tests/test_ec2/test_elastic_ip_addresses.py
@@ -110,29 +110,89 @@ def test_eip_associate_vpc():
 
     instance.terminate()
 
+@mock_ec2
+def test_eip_associate_network_interface():
+    """Associate/Disassociate EIP to NIC"""
+    conn = boto.connect_vpc('the_key', 'the_secret')
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+    eni = conn.create_network_interface(subnet.id)
+
+    eip = conn.allocate_address(domain='vpc')
+    eip.network_interface_id.should.be.none
+
+    with assert_raises(EC2ResponseError) as cm:
+        conn.associate_address(network_interface_id=eni.id)
+    cm.exception.code.should.equal('MissingParameter')
+    cm.exception.status.should.equal(400)
+    cm.exception.request_id.should_not.be.none
+
+    conn.associate_address(network_interface_id=eni.id, allocation_id=eip.allocation_id)
+    eip = conn.get_all_addresses(addresses=[eip.public_ip])[0]  # no .update() on address ):
+    eip.network_interface_id.should.be.equal(eni.id)
+    conn.disassociate_address(association_id=eip.association_id)
+    eip = conn.get_all_addresses(addresses=[eip.public_ip])[0]  # no .update() on address ):
+    eip.network_interface_id.should.be.equal(u'')
+    eip.association_id.should.be.none
+    eip.release()
+    eip = None
+
 @mock_ec2
 def test_eip_reassociate():
     """reassociate EIP"""
     conn = boto.connect_ec2('the_key', 'the_secret')
 
-    reservation = conn.run_instances('ami-1234abcd')
-    instance = reservation.instances[0]
+    reservation = conn.run_instances('ami-1234abcd', min_count=2)
+    instance1, instance2 = reservation.instances
 
     eip = conn.allocate_address()
-    conn.associate_address(instance_id=instance.id, public_ip=eip.public_ip)
+    conn.associate_address(instance_id=instance1.id, public_ip=eip.public_ip)
 
+    # Same ID is idempotent
+    conn.associate_address(instance_id=instance1.id, public_ip=eip.public_ip)
+
+    # Different ID detects resource association
     with assert_raises(EC2ResponseError) as cm:
-        conn.associate_address(instance_id=instance.id, public_ip=eip.public_ip, allow_reassociation=False)
+        conn.associate_address(instance_id=instance2.id, public_ip=eip.public_ip, allow_reassociation=False)
     cm.exception.code.should.equal('Resource.AlreadyAssociated')
     cm.exception.status.should.equal(400)
     cm.exception.request_id.should_not.be.none
 
-    conn.associate_address.when.called_with(instance_id=instance.id, public_ip=eip.public_ip, allow_reassociation=True).should_not.throw(EC2ResponseError)
+    conn.associate_address.when.called_with(instance_id=instance2.id, public_ip=eip.public_ip, allow_reassociation=True).should_not.throw(EC2ResponseError)
 
     eip.release()
     eip = None
 
-    instance.terminate()
+    instance1.terminate()
+    instance2.terminate()
+
+@mock_ec2
+def test_eip_reassociate_nic():
+    """reassociate EIP"""
+    conn = boto.connect_vpc('the_key', 'the_secret')
+
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+    eni1 = conn.create_network_interface(subnet.id)
+    eni2 = conn.create_network_interface(subnet.id)
+
+    eip = conn.allocate_address()
+    conn.associate_address(network_interface_id=eni1.id, public_ip=eip.public_ip)
+
+    # Same ID is idempotent
+    conn.associate_address(network_interface_id=eni1.id, public_ip=eip.public_ip)
+
+    # Different ID detects resource association
+    with assert_raises(EC2ResponseError) as cm:
+        conn.associate_address(network_interface_id=eni2.id, public_ip=eip.public_ip)
+    cm.exception.code.should.equal('Resource.AlreadyAssociated')
+    cm.exception.status.should.equal(400)
+    cm.exception.request_id.should_not.be.none
+
+    conn.associate_address.when.called_with(network_interface_id=eni2.id, public_ip=eip.public_ip, allow_reassociation=True).should_not.throw(EC2ResponseError)
+
+    eip.release()
+    eip = None
 
 @mock_ec2
 def test_eip_associate_invalid_args():
diff --git a/tests/test_ec2/test_elastic_network_interfaces.py b/tests/test_ec2/test_elastic_network_interfaces.py
index 49d4c81e5..1a6ac1714 100644
--- a/tests/test_ec2/test_elastic_network_interfaces.py
+++ b/tests/test_ec2/test_elastic_network_interfaces.py
@@ -1,5 +1,10 @@
 from __future__ import unicode_literals
+# Ensure 'assert_raises' context manager support for Python 2.6
+import tests.backport_assert_raises
+from nose.tools import assert_raises
+
 import boto
+from boto.exception import EC2ResponseError
 import sure  # noqa
 
 from moto import mock_ec2
@@ -7,4 +12,115 @@ from moto import mock_ec2
 
 @mock_ec2
 def test_elastic_network_interfaces():
-    pass
+    conn = boto.connect_vpc('the_key', 'the_secret')
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+    eni = conn.create_network_interface(subnet.id)
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(1)
+    eni = all_enis[0]
+    eni.groups.should.have.length_of(0)
+    eni.private_ip_addresses.should.have.length_of(0)
+
+    conn.delete_network_interface(eni.id)
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(0)
+
+    with assert_raises(EC2ResponseError) as cm:
+        conn.delete_network_interface(eni.id)
+    cm.exception.code.should.equal('InvalidNetworkInterfaceID.NotFound')
+    cm.exception.status.should.equal(400)
+    cm.exception.request_id.should_not.be.none
+
+
+@mock_ec2
+def test_elastic_network_interfaces_subnet_validation():
+    conn = boto.connect_vpc('the_key', 'the_secret')
+
+    with assert_raises(EC2ResponseError) as cm:
+        conn.create_network_interface("subnet-abcd1234")
+    cm.exception.code.should.equal('InvalidSubnetID.NotFound')
+    cm.exception.status.should.equal(400)
+    cm.exception.request_id.should_not.be.none
+
+
+@mock_ec2
+def test_elastic_network_interfaces_with_private_ip():
+    conn = boto.connect_vpc('the_key', 'the_secret')
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+    private_ip = "54.0.0.1"
+    eni = conn.create_network_interface(subnet.id, private_ip)
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(1)
+
+    eni = all_enis[0]
+    eni.groups.should.have.length_of(0)
+
+    eni.private_ip_addresses.should.have.length_of(1)
+    eni.private_ip_addresses[0].private_ip_address.should.equal(private_ip)
+
+
+@mock_ec2
+def test_elastic_network_interfaces_with_groups():
+    conn = boto.connect_vpc('the_key', 'the_secret')
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+    security_group1 = conn.create_security_group('test security group #1', 'this is a test security group')
+    security_group2 = conn.create_security_group('test security group #2', 'this is a test security group')
+    conn.create_network_interface(subnet.id, groups=[security_group1.id,security_group2.id])
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(1)
+
+    eni = all_enis[0]
+    eni.groups.should.have.length_of(2)
+    set([group.id for group in eni.groups]).should.equal(set([security_group1.id,security_group2.id]))
+
+    conn.modify_network_interface_attribute(eni.id, 'groupset', [security_group1.id])
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(1)
+
+    eni = all_enis[0]
+    eni.groups.should.have.length_of(1)
+    eni.groups[0].id.should.equal(security_group1.id)
+
+
+@mock_ec2
+def test_elastic_network_interfaces_filtering():
+    conn = boto.connect_vpc('the_key', 'the_secret')
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+
+    security_group1 = conn.create_security_group('test security group #1', 'this is a test security group')
+    security_group2 = conn.create_security_group('test security group #2', 'this is a test security group')
+
+    eni1 = conn.create_network_interface(subnet.id, groups=[security_group1.id,security_group2.id])
+    eni2 = conn.create_network_interface(subnet.id, groups=[security_group1.id])
+    eni3 = conn.create_network_interface(subnet.id)
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(3)
+
+    # Filter by ENI ID
+    enis_by_id = conn.get_all_network_interfaces(filters={'network-interface-id':eni1.id})
+    enis_by_id.should.have.length_of(1)
+    set([eni.id for eni in enis_by_id]).should.equal(set([eni1.id]))
+
+    # Filter by Security Group
+    enis_by_group = conn.get_all_network_interfaces(filters={'group-id':security_group1.id})
+    enis_by_group.should.have.length_of(2)
+    set([eni.id for eni in enis_by_group]).should.equal(set([eni1.id,eni2.id]))
+
+    # Filter by ENI ID and Security Group
+    enis_by_group = conn.get_all_network_interfaces(filters={'network-interface-id':eni1.id, 'group-id':security_group1.id})
+    enis_by_group.should.have.length_of(1)
+    set([eni.id for eni in enis_by_group]).should.equal(set([eni1.id]))
+
+    # Unsupported filter
+    conn.get_all_network_interfaces.when.called_with(filters={'not-implemented-filter': 'foobar'}).should.throw(NotImplementedError)
+
diff --git a/tests/test_ec2/test_instances.py b/tests/test_ec2/test_instances.py
index 747df202d..e0436fdf2 100644
--- a/tests/test_ec2/test_instances.py
+++ b/tests/test_ec2/test_instances.py
@@ -233,12 +233,86 @@ def test_run_instance_with_instance_type():
 
 @mock_ec2
 def test_run_instance_with_subnet():
-    conn = boto.connect_ec2('the_key', 'the_secret')
-    reservation = conn.run_instances('ami-1234abcd',
-                                     subnet_id="subnet-abcd1234")
+    conn = boto.connect_vpc('the_key', 'the_secret')
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+    reservation = conn.run_instances('ami-1234abcd', subnet_id=subnet.id)
     instance = reservation.instances[0]
 
-    instance.subnet_id.should.equal("subnet-abcd1234")
+    instance.subnet_id.should.equal(subnet.id)
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(1)
+
+
+@mock_ec2
+def test_run_instance_with_nic_autocreated():
+    conn = boto.connect_vpc('the_key', 'the_secret')
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+    security_group1 = conn.create_security_group('test security group #1', 'this is a test security group')
+    security_group2 = conn.create_security_group('test security group #2', 'this is a test security group')
+    private_ip = "54.0.0.1"
+
+    reservation = conn.run_instances('ami-1234abcd', subnet_id=subnet.id,
+                                                     security_groups=[security_group1.name],
+                                                     security_group_ids=[security_group2.id],
+                                                     private_ip_address=private_ip)
+    instance = reservation.instances[0]
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(1)
+    eni = all_enis[0]
+
+    instance.interfaces.should.have.length_of(1)
+    instance.interfaces[0].id.should.equal(eni.id)
+
+    instance.subnet_id.should.equal(subnet.id)
+    instance.groups.should.have.length_of(2)
+    set([group.id for group in instance.groups]).should.equal(set([security_group1.id,security_group2.id]))
+
+    eni.subnet_id.should.equal(subnet.id)
+    eni.groups.should.have.length_of(2)
+    set([group.id for group in eni.groups]).should.equal(set([security_group1.id,security_group2.id]))
+    eni.private_ip_addresses.should.have.length_of(1)
+    eni.private_ip_addresses[0].private_ip_address.should.equal(private_ip)
+
+
+@mock_ec2
+def test_run_instance_with_nic_preexisting():
+    conn = boto.connect_vpc('the_key', 'the_secret')
+    vpc = conn.create_vpc("10.0.0.0/16")
+    subnet = conn.create_subnet(vpc.id, "10.0.0.0/18")
+    security_group1 = conn.create_security_group('test security group #1', 'this is a test security group')
+    security_group2 = conn.create_security_group('test security group #2', 'this is a test security group')
+    private_ip = "54.0.0.1"
+    eni = conn.create_network_interface(subnet.id, private_ip, groups=[security_group1.id])
+
+    # Boto requires NetworkInterfaceCollection of NetworkInterfaceSpecifications...
+    #   annoying, but generates the desired querystring.
+    from boto.ec2.networkinterface import NetworkInterfaceSpecification, NetworkInterfaceCollection
+    interface = NetworkInterfaceSpecification(network_interface_id=eni.id, device_index=0)
+    interfaces = NetworkInterfaceCollection(interface)
+    # end Boto objects
+
+    reservation = conn.run_instances('ami-1234abcd', network_interfaces=interfaces,
+                                                     security_group_ids=[security_group2.id])
+    instance = reservation.instances[0]
+
+    instance.subnet_id.should.equal(subnet.id)
+
+    all_enis = conn.get_all_network_interfaces()
+    all_enis.should.have.length_of(1)
+
+    instance.interfaces.should.have.length_of(1)
+    instance_eni = instance.interfaces[0]
+    instance_eni.id.should.equal(eni.id)
+
+    instance_eni.subnet_id.should.equal(subnet.id)
+    instance_eni.groups.should.have.length_of(2)
+    set([group.id for group in instance_eni.groups]).should.equal(set([security_group1.id,security_group2.id]))
+    instance_eni.private_ip_addresses.should.have.length_of(1)
+    instance_eni.private_ip_addresses[0].private_ip_address.should.equal(private_ip)
 
 
 @mock_ec2