This ETS contains the Test Suite Structure (TSS) and Test Purposes (TPs) to test the TETRA security protocols for Voice + Data (V+D) and Direct Mode (DM). The TPs presented in this ETS are applicable to TETRA terminals supporting security as specified in ETS 300 392-2 [1]@ ETS 300 392-7 [2] and ETS 300 396-6 [3]. The objective of this test specification is to provide a basis for approval tests for TETRA equipment giving a high probability of air interface inter-operability between different manufacturer's TETRA equipment. The ISO standard for the methodology of conformance testing@ ISO/IEC 9646-1 [5] and ISO/IEC 9646-2 [6]@ as well as the ETSI methodology for conformance testing@ ETS 300 406 [4]@ are used as the basis for the test methodology.