A service implemented at a first isolated virtual network of a provider network is added to a database of privately-accessible services. Configuration changes that enable network packets to flow between the first isolated virtual network and a second isolated virtual network without utilizing a network address accessible from the public Internet are implemented. Service requests originating at the second isolated virtual network are transmitted to the first isolated virtual network via private pathways of the provider network. Metrics corresponding to service requests directed from the second isolated network to the service are collected and provided to the respective owners of one or both isolated virtual networks.