Tetreault served as the Executive Director of the Housing Opportunities Commission (HOC) of Montgomery County, Maryland from August 1971 through June 1995. It was his leadership during this 24 years, that earmarks Tetreault’s greatest contribution to the affordable housing industry. In the early 1970’s, Tetreault created and executed the first, and most progressive local housing in the country, by adopting a new inclusionary ordinance and progressive policy called “inclusionary zoning”. Montgomery County is still the oldest, and by far the nation’s largest inclusionary zoning program—a policy that requires real estate developers to set aside a portion of the homes they build to be rented or sold at below-market prices. Tetreault’s game changing focus on deconcentrating poverty in the early years, was brought about by eschewing large-scale public housing projects in favor of placing scattered-site public housing units and two- or three-story family developments throughout the county’s many neighborhoods.
In 2005, Tetreault continued his efforts in inclusionary policy, by establishing the Innovative Housing Institute, a 501(c)3 non-profit that continued to spread the success of Montgomery County’s program by providing assistance to other housing agencies at a national level, which has now spread, to date, to over one hundred high-cost housing markets in California, Massachusetts, New Jersey, Delaware, Florida, New York City, Santa Fe, New Mexico, Denver and Boulder, Colorado; the greater Washington, D.C., metro area; and Burlington, Vermont. Tetreault founded the Innovative Housing Institute with accomplished thought leaders as David Rusk, the author of Inside Game, Outside Game and Cities Without Suburbs. His continued efforts through IHI, founded the very first national conference on inclusionary zoning, partnering with the National Housing Conference, Business and Professional People for the Public Interest, and PolicyLink. For three years, Tetreault and IHI continued to host and spearhead this national conference, which has led the way for Grounded Solutions Network to continue his efforts.
Tetreault currently is advising the Executive Director of the District of Columbia Housing Authority on complex real estate transactions to revitalize several public housing properties into mixed income developments. Tetreault served as 1st Vice President of the National Housing Conference and as a member of the Board of Directors. He co-founded the Association of Local Housing Finance Agencies, now known as the National Association of Local Housing Finance Agencies (NALHFA) and was its national president in 1983 and 1984. Currently Tetreault serves on the Board of Directors of two non-profit housing corporations, Homes for America and the Outer Banks (NC) Community Development Corporation, which he helped form.