The GSA Defense Advanced Research Projects Agency’s (DARPA) new headquarters is part of a new mixed-use project, Founders Square. Participating in the LEED-ND pilot program and adjacent to Ballston Commons mall, Founders Square encompasses two residential towers, one office tower, and one GSA/office tower. STUDIO39’s site design responds to the interaction between active and passive pedestrian spaces and the scale of spaces between the towers, while adhering to the GSA’s strict ATFP security requirements. The current design includes undulating grassed berms intersected by corten steel walls. The plaza spaces are above underground parking.