Abstract: Originally, mobility in IP networks has been realised in a large scale only denoted by macro-mobility or portability. With the demand of terminal mobility without the interruption of ongoing sessions new mechanisms on the IP layer and below are needed to support the actual movement of a terminal, which comprises the fast association to access points in a small-scale or micro-mobility. Fast handover is a task that requires enhancements of the standard IETF protocol 'Mobile IP'. This task most probably also includes lower layer involvement. Within the context of the 5th European research framework IST (Information Society Technology) the project MIND (Mobile IP based Networks Development) develops and extends concepts for a broadband multimedia IP-based radio access network. Approaches for handover realisation over multiple air-interfaces, also commonly known as vertical handover, are presented to maximise efficiency and performance while keeping complexity and air-interface burden as low as possible. Requirements and proposed features to allow for seamless handover are analysed for UMTS and HIPERLAN/2 radio technologies for exemplary purposes. In this paper we present an approach for complex L2-assisted L3-controlled handover of active connections, adaptation of media to changed bandwidth, QoS re-negotiation and re-authentication with minimum signalling overhead, as also covered within the MIND project. These concepts are presented and analysed with respect to efficiency whereby benefits of the proposed architecture are highlighted.