GRP, Honorary ASLA has worked on sustainable community development for more than 35 years initially as a policy consultant to government and over the last twenty years as the founder and president of Green Roofs for Healthy Cities, and the Co-Founder of the charitable Green Infrastructure Foundation, and the World Green Infrastructure Network.

He has edited and published the quarterly www.livingarchitecturemonitor.com magazine for twenty years, written several books on green roofs and walls, and delivered keynote addresses and papers around the world all emphasizing the importance of investing in living technologies in, on and around our buildings. He is the father of the green roof industry in North America having lead the development of the Green Roof Professional (GRP) training and accreditation and having advocated for green roof policy establishment in cities like Washington DC, Toronto, Chicago, New York, Denver, San Francisco and Portland.