Dive summary:

• In looking at the effect when governments at all levels decide to build green buildings for public use, a Harvard Business School study finds that can change the marketplace.
• Timothy Simcoe from Boston University and and Michael W. Toffelfrom Harvard looked at what happened in California between 2001 and 2008, when some local governments decided that public spending would go into green buildings – usually using LEED as a guide.
• They found that in cities that had gone green for public projects had about 90% more private-sector green projects than similar cities that were not using green policies for public construction, and the effect spilled over into neighboring communities.

From the article:

"Committing in advance to build green does have spillover effects for private adoption green-building practices, for both the supply of inputs such as contractors and the demand for buildings that are measurably green. ..."