The landscape architecture firm of Frederick Law Olmsted, and later of his sons John Charles Olmsted and Frederick Law Olmsted Jr. (known as the Olmsted Brothers), produced designs and plans for hundreds of parks, campuses and other projects throughout the United States and Canada. Together, these works totaled 355.

The most famous designer of parks in history is undoubtedly Frederick Law Olmsted (1822–1903), often referred to as the "father of American landscape architecture." His most iconic work is Central Park in New York City, which he co-designed with Calvert Vaux. Olmsted believed that public parks should be "democratic spaces" accessible to all citizens, providing a necessary escape from the pressures of urban life. His portfolio is vast, including Prospect Park in Brooklyn, the "Emerald Necklace" in Boston, and the grounds of the U.S. Capitol. Beyond Olmsted, other influential figures include Lancelot "Capability" Brown, who transformed the English landscape in the 18th century with his "naturalistic" style, and André Le Nôtre, the mastermind behind the formal Gardens of Versailles. In 2026, Olmsted's philosophy of "pastoral" and "picturesque" scenery remains the foundational blueprint for urban green spaces worldwide.