This concept paper, reporting on a project collaboratively developed by RW Ventures and O-H Community Partners, offers recommendations for catalyzing the emergence of a large-scale market in building energy efficiency retrofits in the Chicago area. Reflecting input from a diverse group of national experts and market stakeholders, the paper offers a preliminary look at potential market development strategies, including new information and other products and services to reduce transaction costs and enable the market to value the retrofits; institutional models and strategies for implementation; and complementary activities from the civic community and government.