The Family Assistance Plan (FAP) was a welfare program introduced by President Richard Nixon in August 1969, which aimed to implement a negative income tax for households with working parents. The FAP was influenced by President Lyndon B. Johnson's War on Poverty program that aimed to expand welfare across all American citizens, especially for working-class Americans. Nixon intended for the FAP to replace existing welfare programs such as the Aid to Assist Families with Dependent Children (AFDC) program as a way to attract conservative voters that were beginning to become wary of welfare while maintaining middle-class constituencies. The FAP specifically provided aid assistance to working-class Americans, dividing benefits based on age, the number of children, family income, and eligibility. Initially, the Nixon administration thought the FAP legislation would easily pass through the House of Representatives and the more liberal Senate, as both chambers were controlled by the Democratic Party. In June 1971, the FAP under the bill H.R. 1 during the 92nd Congress, passed in the House of Representatives. However, from December 1971 to June 1972 H.R.1 bill that included the FAP underwent scrutiny in the Senate chamber, particularly by the Senate Finance Committee controlled by the conservative Democrats, while the Republicans were also reluctant on passing the program. Eventually, on October 5 of 1972, a revised version of H.R.1 passed the Senate with a vote of 68-5 that only authorized funding for FAP testing before its implementation. During House-Senate reconciliation, before Nixon signed the bill on October 15, 1972, the entire provision on FAP was dropped. The FAP enjoyed broad support from Americans across different regions. Reception towards the program varied across racial, regional, income, and gender differences. The FAP is best remembered for beginning the rhetoric against the expansion of welfare that was popular during the New Deal. It initiated the support for anti-welfare conservative movements that became mainstream in American political discourse during the Reagan era.

In economics, a negative income tax (NIT) is a system which reverses the direction in which tax is paid for incomes below a certain level; in other words, earners above that level pay money to the state while earners below it receive money, as shown by the blue arrows in the diagram. NIT was proposed by Juliet Rhys-Williams while working on the Beveridge Report in the early 1940s and popularized by Milton Friedman in the 1960s as a system in which the state makes payments to the poor when their income falls below a threshold, while taxing them on income above that threshold. Together with Friedman, supporters of NIT also included James Tobin, Joseph A. Pechman, and Peter M. Mieszkowski, Jim Gray and even then-President Richard Nixon, who suggested implementation of modified NIT in his Family Assistance Plan. After the increase in popularity of NIT, an experiment sponsored by the US government was conducted between 1968 and 1982 on effects of NIT on labour supply, income, and substitution effects.