This handbook provides additional information for the application of the testing standard ECSS-E-ST-10-03 to a space system product. This handbook does not contain requirements and therefore cannot be made applicable. In case of conflict between the standard and this handbook, the standard prevails. This handbook is relevant for both the customer and the supplier of the product during all project phases. To facilitate the cross-reference, this handbook follows as much as practical, the structure of the standard even if, as written in the Introduction, some tests are described in the Annexes to allow a better comprehensive view. Where test material is already covered in other ECSS handbook, this document refers to them instead of duplicating the information, this is the case of ECSS-E-HB-32-25 Mechanical shock design and verification handbook and the various parts of ECSS-E-HB-31-01 Thermal design handbook . As the Standard applies to different products at different product levels of the space segment, the space segment equipment and the space segment elements. In the testing standard the requirements applicable to each level are addressed in different chapters clearly identified. The standard clearly states that it is not applicable to other segment (launch and ground) as well as software; as a consequence, no pre-tailoring matrix is needed. Moreover, as per testing standard, this handbook does not contain guidelines for constellation programmes. Testing aspects are derived from the verification approach covered in the ECSS-E-ST-10-02 and in its corresponding handbook ECSS-E-HB-10-02. The application of the requirements of the standard to a particular project is intended to result in effective product verification and consequently to a high confidence in achieving successful product operations for the intended use, in this respect this handbook has the goal to help reaching these objectives.