 One of its first campaigns was helping to halt the filling of San Francisco Bay for development.In 1969, the organization was renamed People for Open Space to reflect the organization's additional interest in preserving ranch lands, agricultural lands, and wildlife preserves.In the 1970s, People for Open Space helped to establish a public park district called the Midpeninsula Regional Open Space District (1972), as well as Suisun Marsh (1974).