A system, method and computer-readable media for managing contact information via a network-based interface. A network resource transmits a data request to a contact information processing service. The contact information processing service processes the data request in accordance with the parameters included in the data request and information maintained by the contact information processing service. Examples of the processing facilitated by the contact information processing service include contact identification routines, contact verification routines, group-based information routines, and communication information routines. The contact information processing service returns the results to the requesting network resource.