Carnegie Endowment for International Peace sought an interior renovation of its 1989 building, located on Washington DC’s historic Embassy Row. Enhanced by light, the whitewashed environment is now engaging, inviting, and peaceful. The transformation of the space began with an important architectural intervention – removing a part of the 2nd floor to transform the lobby into a 2-story volume, in which a new, stretched membrane ceiling is backed with a dynamic white LED matrix, offering a luminous, tunable white “sky” space. This is coupled with an elegant communicating stair, set against a light-grazed, fluted porcelain wall. This internal vertical expansion sets the tone of the visitor’s experience, in which light serves to broaden and deepen the renewed public spaces in this global think tank.