A method and system for integrating media independent handover (MIH) under IEEE 802.21 and unlicensed mobile access (UMA) are disclosed. A public land mobile network (PLMN) and an unlicensed mobile access network (UMAN) are concurrently deployed. UMA is supported such that a multi-mode wireless transmit/receive unit (WTRU) may access the UMAN to receive PLMN services through the UMAN. MIH entities are included both in the VVTRU and the UMAN and the MIH entity of the WTRU monitors handover events and information and generates a handover trigger for handover between the PLMN and the UMAN. The MIH entity in the UMAN interacts with the MIH entity of the WTRU to report a remote event, handover information and command.