In 1868, Frederick Law Olmsted, America's first landscape architect, envisioned for Buffalo a design that became the nation's first complete system of urban parks and parkways, and is now listed on the National Register of Historic Places. In partnership with the City of Buffalo, the Conservancy is responsible for the care and maintenance of the system, which totals 850 acres and is composed of six major parks, seven parkways and eight landscaped circles.

The Conservancy is the first nonprofit organization to manage and operate an entire historic park system. The membership-based organization's mission is to promote, preserve, restore, enhance, and maintain the region's Olmsted-designed parks and parkways. In 2014, the American Planning Association recognized Delaware Park as one of the great places in America. Most recently, The Guardian, the international news source based in the United Kingdom, cited the Buffalo Olmsted Park System as one of the top 10 green urban spaces in the world.