The main objective of this report is to describe methods and tools for assessment of electronic warfare. The report is primarily focused at describing activities that have been accomplished within the project Assessment of Electronic Warfare at the Division of Defence Analysis within the Swedish Defence Research Agency, mainly between the years 2000 and 2002. The focus is on methods used and tools developed. The report also contains a general description of electronic warfare and a discussion concerning electronic warfare is association with the development of the Swedish Armed Forces. In addition to that there are sections about technology development in areas relevant to electronic warfare and a general discussion on assessment. Another objective of this report is to make a contribution to the understanding of opportunities and limitations offered by electronic warfare and may hence be of use e.g. for operations analysts.