Woolworth sit-in, Jackson, MS. May 28, 1963

In sit-ins, protesters usually seat themselves at a strategic location (inside a restaurant, in a street to block it, in a government or corporate office, and so on). They remain until they are evicted, usually by force, or arrested, or until their requests have been met. Sit-ins have historically been a highly successful form of protest because they cause disruption that draws attention to the protest and by proxy the protesters' cause. They are a non-violent way to effectually shut down an area or business. The forced removal of protesters, and sometimes the use of violence against them, often arouses sympathy from the public, increasing the chances of the demonstrators reaching their audience.

Sit-ins were an integral part of the nonviolent strategy of civil disobedience and mass protests that eventually led to passage of the Civil Rights Act of 1964 which ended legally-sanctioned racial segregation in the United States and also passage of the Voting Rights Act of 1965 that struck down many racially-motivated barriers used to deny voting rights to non-whites.