Recognizing that the U.S. has failed to formulate and implement an integrated national strategy addressing environmental sustainability and energy conservation, this paper proposes cross-sector collaboration among the business, government, and nonprofit sectors as a necessary approach. This paper draws on institutional theory to explain differences among the sectors, and the challenges posed in forming cross-sector collaboration. Scenarios of sustainability initiatives are presented along with potential inhibitors to explain barriers posed by inter- and intra-sector institutional differences. This paper proposes that prolonged urgency, supported by ongoing turbulent conditions economically, socially, and environmentally, is necessary to form cross-sector collaboration at a supraorganizational level.