Abstract This paper uses path overlap, an innovative measure of functional proximity, to examine how physical space shaped the formation and success of scientific collaborations among the occupants of two academic research buildings. We use research administration data on human subject protection, animal use management, and grant funding applications to construct new measures of collaboration formation and success. The “functional zones” investigators occupy in their buildings are defined by the shortest walking paths among assigned laboratory and office spaces, and the nearest elevators, stairs, and restrooms. When two investigators traverse paths with greater overlap, both their propensity to form new collaborations and to win grant funding for their joint work increase. This effect is robust across two very differently configured buildings. Implications for scientific collaboration and the design and allocation of research space are considered.