The Women's Army Corps (WAC) was a special unit of the United States Army during World War II. It enlisted women.

As many as 150,000 American women served in the corps during World War II. They were the first women other than nurses to serve with the Army. While conservative opinion in the leadership of the Army and public opinion generally was initially opposed to women serving in uniform, the shortage of men necessitated a new policy.

During the same time period, other branches of the US military had similar women's units including the Navy WAVES and the Women's Auxiliary Air Force.