This standard addresses the requirements for performing verification by testing of space segment elements and space segment equipment on ground prior to launch. The document is applicable for tests performed on qualification models, flight models (tested at acceptance level) and protoflight models.The standard provides:•Requirements for test programme and test management,•Requirements for retesting,•Requirements for redundancy testing,•Requirements for environmental tests,•General requirements for functional and performance tests,NOTE Specific requirements for functional and performance tests are not part of this standard since they are defined in the specific project documentation.•Requirements for qualification, acceptance, and protoflight testing including qualification, acceptance, and proto-fight models’ test margins and duration,•Requirements for test factors, test condition, test tolerances, and test accuracies,•General requirements for development tests pertinent to the start of the qualification test programme,NOTE Development tests are specific and are addressed in various engineering discipline standards.•Content of the necessary documentation for testing activities (e.g. DRD).Due to the specific aspects of the following types of test, this Standard does not address:•Space system testing (i.e. testing above space segment element), in particular the system validation test,•In-orbit testing,•Testing of space segment subsystems,NOTE Tests of space segment subsystems are often limited to functional tests that, in some case, are run on dedicated models. If relevant, qualification tests for space segment subsystems are assumed to be covered in the relevant discipline standards.•Testing of hardware below space segment equipment levels (including assembly, parts, and components),•Testing of stand-alone software,NOTE For verification of flight or ground software, ECSS-E-ST-40 and ECSS-Q-ST-80 apply.•Qualification testing of two-phase heat transport equipment,NOTE For qualification testing of two-phase heat transport equipment, ECSS-E-ST-31-02 applies.•Tests of launcher segment, subsystem and equipment, and launch facilities,•Tests of facilities and ground support equipment,•Tests of ground segment.This standard may be tailored for the specific characteristic and constrains of a space project in conformance with ECSS-S-ST-00. Annex D gives guidelines for performing this tailoring.