Someone may feel difficult to distinguish the terms "Design Review", "Design Verification" and "Design Validation" in ISO 9001 as they look like similiar. In fact, they can be combined into one step. But in the most cases, it is better to consider them differently. Ref. to ISO 9004-1: 1994, clause 8.4.1, it is clearly stated that Design Review should be "distinguish from a project progress meeting". As ISO 9004-1 is not a standard for certification, I think most of the organization may miss this concept. As stated in ISO 9004-1, the main purposes for the Design Reviews are "identify and anticipate problem areas and inadequacies, and initiate corrective actions". In general, Design Reviews can be performed by the means of discussion, comparisons and auditing. Testing, experiment or demonstration is not a must for Design Review. Although there is no restriction on how many times of Design Review must be done throughout the design process, it is better to perform several Design Reviews at different stages of design than to perform only one Design Review just before releasing the final design. Design Verification includes all the elements of Design Review but also includes some data and objective reviews such as alternative calculations, testing and demonstrations by the means of models or phototype. Of course, test programme includes testing procedures, testing environment and acceptance criteria should be clearly defined. In addition, as stated in ISO 9004-1, "independent verification" is strongly recommended so that Design Verification may be better not performed by the designer. In general, Design Verification should be done after a number of Design Reviews. After a number of Design Verifications is done, Design Validation can be performed. As stated in ISO 9004-1, Design Validation can be done by the means of fault or risk analysis. Testing of a number of samples is recommended so that adequate statistical confidence can be provided. In most case, Design Validation should be done by samples of proposed products (or similiar product if same materials cannot be used) testing in control condition or environment such as proposed usage environment. If the proposed products can be used in different ways, several Design Validations should be done. Similiar to Design Verification, independent Design Validation is recommended. Finally, if the organization is planned to perform only one Design Review / Verification / Validation throughout the design process, it must be done just before releasing the final design and no design change can be done after. If design changes are done afterward, the Design Review / Verification / Validation must be repeated. Validation. The assurance that a product, service, or system meets the needs of the customer and other identified stakeholders. It often involves acceptance and suitability with external customers. Contrast with verification." "Verification. The evaluation of whether or not a product, service, or system complies with a regulation, requirement, specification, or imposed condition. It is often an internal process. Contrast with validation."