Ralph Nader (born February 27, 1934) is an American political activist, author, lecturer, and attorney noted for his involvement in consumer protection, environmentalism, and government reform causes. He became famous in the 1960s and 1970s for his book Unsafe at Any Speed, which criticized the automotive industry for its safety record and helped lead to the passage of the National Traffic and Motor Vehicle Safety Act in 1966.

The son of Lebanese immigrants to the United States, Nader attended Princeton University and Harvard Law School. He first came to prominence in 1965 with the publication of the book Unsafe at Any Speed, a highly influential critique of the safety record of American automobile manufacturers. Following the publication of Unsafe at Any Speed, Nader led a group of volunteer law students—dubbed "Nader's Raiders"—in an investigation of the Federal Trade Commission, leading directly to that agency's overhaul and reform.