This paper explores the spatial and temporal patterns of green building in the commercial and institutional sectors in the US. While these buildings are becoming more commonplace, they have yet to reach a critical mass to affect the entire construction industry. Given the potential for green building practices to reduce energy consumption and carbon emissions, the paper seeks to understand the geography of green building. Using multiple metrics, it explains the patterning of geography of LEED and Energy Star certified buildings in the US. Strong evidence is found of clustering at the metropolitan and sub-metropolitan scales. This exploratory research serves as a foundation for future research aimed at specifying the nature of agglomerative processes in green buildings.