The purpose of the present document is to provide Test Suite Structure and Test Purposes (TSSTP) for conformance tests of the conformance test suite for TTCN-3 as defined in ETSI ES 201 873-1 [1]. In the present document only the core language features@ specified in ETSI ES 201 873-1 [1] have been considered but not the tool implementation (see [i.1] and [i.2])@ language mapping (see [i.3]@ [i.4] and [i.5]) and language extension (see e.g. [i.6]@ [i.7] and [i.8]) aspects