The present document is step 3 of a three-step approach to describe a generic Handover Interface (HI) for the provision of lawful interception from a Network Operator@ an Access Provider or a Service Provider (NWO/AP/SvP) to the Law Enforcement Agencies (LEAs). The provision of lawful interception is a requirement of national law@ which is usually mandatory for the operation of any telecommunication service. Step 1 contains the requirements for lawful interception from a users (LEAs) point of view and is published in TS 101 331 [1]. Step 2 describes the derived network functions and the general architecture (or functional model) and is published in ES 201 158 [2]. The present document specifies: the generic flow of information as well as the procedures and information elements@ which are applicable to any future telecommunication network or service; the network/service specific protocols relating to the provision of lawful interception at the Handover Interface (HI)@ for the following networks/services: - switched circuit; and - packet data. The technologies covered in the present document are: GSM@ TETRA@ GPRS@ ISDN@ PSTN@ fixed NGN (including PSTN/ISDN emulation) and fixed IMS PSTN simulation. NOTE: As new networks and/or services are developed@ the present document will be expanded as the relevant standards become available.