The present article analyzes the integration of green building policy and practice with the largest low-income housing production program in the US and the innovativeness of its housing agencies. Drawing on policy innovation literature, panel data and regression analysis are employed to quantify associations between state-level characteristics and the adoption of green building criteria into the Low-Income Housing Tax Credit (LIHTC) program. Results show that, on average, housing agencies have increasingly adopted green building criteria, and most have identified co-benefits from energy-efficient buildings and smart growth. Despite overall progress, the rate of adoption of green building criteria has decreased, few states have comprehensive criteria, and many have dropped important criteria, such as on-site renewable energy generation. Results are consistent with hypotheses derived from the literature and suggest the integration of green building with LIHTC developments is significantly associated with government motivation, financial resources, and exogenous characteristics that affect the demand for green building. Future research should explore organization-level factors that affect environmental policy innovation. It is recommended that LIHTC housing agencies require compliance with green building rating systems and periodically reconfigure green building criteria based on planned evolutionary change, data-driven strategies, and life-cycle analyses towards zero net energy consumption.