This report describes experiences from participation in the NATO task groups Assessment of Possible Disruptive Technologies for Defence and Security (SAS- 062) and Disruptive Technology Assessment Game - Evolution and Validation (SAS-082). A disruptive technology is defined in the following way: "A Disruptive Technology stands for a technological development which changes the conduct of operations (including the rules of engagement) significantly within short time and thus alters the long-term goals for concepts, strategy and planning". The work of the two task groups focused on both methodology development (developing a methodology for technology assessment) and on using this methodology to draw conclusions regarding disruptive technology development. The focus of this report lies solely on presenting and discussing the proposed methodology. This is also the most important result of the two task groups, the conclusions regarding technologies must be seen as preliminary. The report describes the elements of the methodology as well as the different roles military personnel, technology experts and analysts had in the task groups. The methodology for technology assessment developed within the NATO task groups SAS-062 and SAS-082 is interesting and should be possible to use, perhaps in a downsized form, in Sweden. The task group SAS-082 proposed a way to maintain the knowledge and ability to use the methodology within NATO. Key parts of the methodology has also been used within the Nordic defence co-operation (NORDEFCO) during 2012 and 2013.