A networking policy implementation for a multi-virtual machine appliance that includes a method for selecting a network implementation by applying a network policy to existing network configurations within a virtualization environment of a computing device. A control program that executes within the virtualization environment, receives an event notification generated by a virtual machine in response to a lifecycle event. The control program, in response to receiving the notification, invokes a policy engine that applies a network policy to existing network configurations of the virtualization environment. This network policy can correspond to the virtual machine or to a network object connected to virtual interface objects of the virtual machine. The policy engine then identifies an existing network configuration that has attributes which satisfy the network policy, and selects a network implementation that satisfies the network policy and the network configuration.