From green roofs to community gardens and energy efficiency to smart grids, Greater Philadelphia has established itself as an early adopter and valuable innovator when it comes to sustainable design, building, business and communities. The Philly-based Pennsylvania Horticulture Society and the City's Office of Sustainability Greenworks Philadelphia, along with community development initiatives across the city and suburbs, from both the non-profit and government sectors, are responsible for one of the nation's most robust examples of urban greening.