The present document specifies interoperability Test Descriptions (TDs) for Inter-IMS Network to Network Interface (II-NNI) interoperability testing for the Rich Communication Suite (RCS) related services based on Release 2 of the RCS Functional Description [8]@ the RCS Service Definition [9] and the Technical Realization [10] documents. The Stage 3 Session Initiation Protocol (SIP) and Session Description Protocol (SDP) standard@ TS 124 229 [1] and Inter-IMS Network to Network Interface@ TS 129 165 [7] define the functionalities on which the RCS services are based. TDs have been specified on the basis of the Test Purposes (TPs) and Test Suite Structure (TSS) presented in TS 186 011-1 [2]. TP fragments presented in the present document as part of TDs are defined using the TPLan notation of ES 202 553 [5]. TDs have been written based on the test specification framework described in TS 102 351 [3] and the interoperability testing methodology defined in TS 102 237-1 [4]@ i.e. interoperability testing with a conformance relation. NOTE: Requirements pertaining to a UE or an AS implementation or IMS core network requirements that can only be observed at the interface between UE and IMS CN are explicitly not within the scope of the present document. The latter requirements have been dealt with from a UE and conformance perspective in TS 134 229 [6].