A wireless communications network includes a first base station system that performs wireless communications according to a first protocol (e.g., 1xEV-DO protocol) and a second base station system that performs wireless communications according to a second, different protocol (e.g., IS-2000). A link is provided between the first and second base station systems to enable a network-initiated handoff procedure. If a source base station system detects that a handoff of a mobile station to a target base station system is required, the source base station system exchanges messaging over the link with the target base station system to perform the handoff. In one example, the handoff is a hard handoff.