Since several years the Swedish Armed Forces are developing a new, NCW inspired C4I system (FMLS 2010). The development activities were run within the framework of FM Ledsyst. The Swedish Defence Research Agency (FOI - project GRU) was assigned to supervise and evaluate the different activities, particularly on the system-of- system level. The task has been to carry on a "accompanying evaluation". In the earlier phases of FM Ledsyst the project GRU has supported the development activities, in the later phases the task has been like a more traditional evaluation. An over all project summing up has been done every sixth month (Synthesis). Considerable efforts have been made to create methods in order to evaluate large-scale experiments. GRU has also carried out a system-of-system evaluation of FM Ledsyst as part of the final report from the FM Ledsyst activities.