The purpose of this environmental impact study of the activities at FOI in Bromma is to supplement an earlier study of FOA 1998 so that the two of them together will form a ground for the environmental work at FOI. In this study we have identified the different activities at FOI in Bromma, analysed them and evaluated their potential environmental impact. The different activities were listed under the following headlines: - research and development (theoretical and experimental research, field trials, design and manufacturing) and - other activities (administration, management of land, constructions and use of premises, travels and transports). In conclusion we find that the largest negative environmental impact is due to management of constructions and use of premises and to travels and transports. In our evaluation of the environmental impact resulting from the results of the research activities at the Aeronautics division in Bromma we have found good possibilities for positive impact.