Reliability, suitability and validity are some of the most important attributes in CGF (Computer Generated Forces)development and deployment. Because of the inherent complexity of human behaviour, resource and cost driven model development reasons and application diversity these key issues are however so far at a stage of infancy. A growing understanding in the CGF and HBR (Human Behaviour Representation)community is that the efforts to model CGF and human behaviour need tailoring with respect to capabilities and constrains given by the requirements specifications of the application. This further stresses the need to explain suitability and validity aspects. To meet this need efficienty appropriate VV&A methodologies are required. This report in short describes a recently developed VV&A methodology, the REVVA methodology, gives an overview of current verification and validation methods and techniques used for the CGF and discusses of the REVVA methods for CGF validation. It finally describes some considerations for the road ahead. To provide an understanding of the problem of CGF validation a review of human behaviour´s history from the psychology has been performed, including the efforts to formulate, declaire and model these phenomena. These theories constitute the foundations for cognitive architectures developed during the last three decades. They are the basis for building simulation models of human behaviour today. This report can not proclaim the REVVA methodology to be the solution for CGF validation. However, useful guidelines are provided by the methodology, e g to build the ToA product and use the tailoring method.