Veri?cation is also concerned with whether the model as designed will satisfy the requirements of the intended application. It examines transformational accuracy, that is, the accuracy of transforming the model’s requirements into a conceptual model and the conceptual model into an executable model. Validation is the process of determining the degree to which the model is an accurate representation of the simulant. The process of validation assesses the accuracy of the models. It examines representational accuracy, that is, the accuracy of representing the simulant in the conceptual model and in the results produced by the executable model. Verification & Validation are fundamental testing processes and are technical in nature. Accreditation, on the other hand, is a decision process and is nontechnical in nature. Accreditation is the of?cial certi?cation by a responsible authority that a model is acceptable for use for a speci?c purpose. Accreditation is concerned with of?cial usability, that is, the determination that the model may be used.