In June 2005 Mayor Gavin Newsom announces San Francisco as the first North American city to host the United Nations World Environment Day.

World Environment Day is a project of the United Nations Environment Program (UNEP). Since its inception in 1972, World Environment Day has given a human face to environmental issues, and promoted an understanding that communities are pivotal to changing attitudes about the environment.

UNEP provides leadership and encourages partnership in caring for the environment by inspiring, informing, and enabling nations and peoples to improve their quality of life without compromising that of future generations.