A IP telephony service allows customers to form user groups. Each user group can include multiple members, each of whom have their own telephony device. When a member of a user group sends an outgoing communication from one of the telephony devices associated with the user group, the service obtains communication handling instructions for the user group. The outgoing communication is then processed in accordance with the handling instructions. This could include sending copies of the outgoing communication to the telephony devices of other members of the user group. This could also include sending the outgoing communication with an origination identifier associated with the user group, rather than an origination identifier associated with the member's telephony device.