Western States Legal Foundation (WSLF) is a nonprofit public-interest organization founded in 1982 that monitors and analyzes U.S. nuclear weapons programs and related technologies. Based in Oakland, California, it focuses particularly on the national nuclear weapons laboratories and examines the effects of nuclear policy on international security, the environment, public health, the economy, and democracy.

WSLF works to abolish nuclear weapons, promote open public environmental review of nuclear technologies, and ensure responsible management of nuclear waste. Its research and analysis covers nuclear weapons policy, research, testing, and production, as well as ballistic missile defense and efforts to militarize outer space. The foundation also assists communities affected by the health and environmental consequences of nuclear weapons production and other nuclear technologies.

Grounded in nonviolence and international and environmental law, WSLF advocates for democratic public decision-making on nuclear and related technologies. It shares research, commentary, legal submissions, educational materials, and event information, and collaborates with peace, legal, and disarmament networks.