Under the GSA Design Excellence Program, EYP was tasked with modernizing the William S. Moorhead Federal Office Building according to LEED for Existing Buildings standards. With 770,000 gross square feet of office space on 22 floors, the building houses 50 different government agencies, each with diverse requirements for space, function, and security. Complex phasing minimized disruption of building occupants. Onsite evaluations, energy modeling, and life-cycle cost analyses guided the design of highly efficient lighting; control system and occupancy sensors; energy-efficient harmonic cancellation-type transformers; and a heat recovery system. EYP also worked with GSA facility managers to review operations and establish new sustainable building operations guidelines for this high-performance building.