Operable Boundary Townhouse/Garden creates a new field of openness excavated out of the lower level of an existing traditional townhouse in Brooklyn Heights. Removing all of the servant spaces from the house at both the garden levle and the parlor floor liberates the space from it's previous secondary status. The traditional boundary between parlor and kitchen is opened through the excavation of a two story space over the dining space and the light aperatures between the parlor and the kitchen which cut into the security of the traditional floor which separates them. The kitchen/dining space becomes an entertaining space and a family space equilivant to the formal parlor spaces overhead. Open to each other as well as the garden, it becomes an open field of occupation rather than a closed relationship of proximity and view.Likewise, the boundary between the garden and the house is opened. The operable window/door floating in the field of glass allows the visual/physical relationship between the garden and the house to fluctuate. Joining the two spaces is a translucent table which slides between interior and exterior. This fluctuation between separation and joining defined by the window/door and table relationship accentuates the capacity of the boundary to reconfigure and define alternate relationships between them.