Progressivism in the United States is a political philosophy and reform movement. Into the 21st century, it advocates policies that are generally considered social democratic and part of the American Left. It has also expressed itself with right-wing politics, such as New Nationalism and progressive conservatism. It reached its height early in the 20th century. Middle/working class and reformist in nature, it arose as a response to the vast changes brought by modernization, such as the growth of large corporations, pollution, and corruption in American politics. Historian Alonzo Hamby describes American progressivism as a "political movement that addresses ideas, impulses, and issues stemming from modernization of American society. Emerging at the end of the nineteenth century, it established much of the tone of American politics throughout the first half of the century."

The New Deal was a series of programs, public work projects, financial reforms, and regulations enacted by President Franklin D. Roosevelt in the United States between 1933 and 1938. Major federal programs and agencies, including the Civilian Conservation Corps (CCC), the Works Progress Administration (WPA), the Civil Works Administration (CWA), the Farm Security Administration (FSA), the National Industrial Recovery Act of 1933 (NIRA) and the Social Security Administration (SSA), provided support for farmers, the unemployed, youth, and the elderly. The New Deal included new constraints and safeguards on the banking industry and efforts to re-inflate the economy after prices had fallen sharply. New Deal programs included both laws passed by Congress as well as presidential executive orders during the first term of the presidency of Franklin D. Roosevelt.