Green building has emerged over the past decade as a robust movement to create high-performance, energy-efficient structures that improve occupant comfort and well-being while minimizing environmental impacts. Supported by organizations such as the U.S. Green Building Council and its Leadership in Energy and Environmental Design (LEED) standards, both public and private entities are increasingly pursuing green buildings in the institutional, commercial, and residential sectors. While this progress is impressive, for a number of reasons it has not included significant numbers of affordable housing projects. These reasons, several of which are unique to affordable housing, include: an almost exclusive focus on "first costs," the existence of per unit cost caps, regulatory rigidity that limits green innovation, and a finance system that fails to recognize the long-term value of green investments.

The United States has almost 90 million residential structures. While few have been built in a sustainable manner, we are nevertheless beginning to see more interest in green or environmentally sustainable housing. Most discussions of sustainable housing focus on the environmental and economic aspects, overlooking the social dimension. Achieving sustainable housing requires a holistic framework, incorporating the economic, environmental, and social dimensions of sustainability in equal parts. Planners must help ensure that social equity is given equal attention during discussions of sustainable housing.

The U.S. Green Building Council's new rating system for Leadership in Energy and Environmental Design in neighborhood development, known as LEED-ND, is coming under fire for not putting a greater emphasis on affordable housing.