Recommendation ITU-T Z.168 defines the mapping rules for Common Object Request Broker Architecture (CORBA) Interface Definition Language (IDL) to TTCN-3 (as defined in Recommendation ITU-T Z.161) to enable testing of CORBA-based systems. The principles of mapping CORBA IDL to TTCN-3 can be also used for the mapping of interface specification languages of other object-/component-based technologies. The specification of other mappings is outside the scope of this Recommendation. This revision of the Recommendation contains amendments, clarifications, corrigenda and editorial corrections.