American New Deal agency, employing millions of job-seekers (mostly men who were not formally educated) to carry out public works projects, including the construction of public buildings and roads. It was established by presidential order, as a key part of the Second New Deal.

The WPA's initial appropriation in 1935 was for $4.9 billion (about 6.7 percent of the 1935 GDP). Headed by Harry Hopkins, the WPA provided paid jobs to the unemployed during the Great Depression in the United States, while building up the public infrastructure of the US, such as parks, schools and roads. Most of the jobs were in construction, building more than 620,000 miles (1,000,000 km) of streets and over 10,000 bridges, in addition to many airports and much housing. The largest single project of the WPA was the Tennessee Valley Authority.

At its peak in 1938, it provided paid jobs for three million unemployed men and women, as well as youth in a separate division, the National Youth Administration. Between 1935 and 1943, the WPA employed 8.5 million people.

Hourly wages were typically set to the prevailing wages in each area.

Full employment, which was reached in 1942 and emerged as a long-term national goal around 1944, was not the goal of the WPA; rather, it tried to provide one paid job for all families in which the breadwinner suffered long-term unemployment.