Coordinates: 38°56′28″N 77°04′27″W / 38.941153°N 77.074188°W / 38.941153; -77.074188

Sidwell Friends School is a Quaker private school located in Washington, D.C. and Bethesda, Maryland in the United States offering pre-kindergarten through secondary school classes. Founded in 1883 by Thomas Sidwell, its motto is "Eluceat omnibus lux" (Let the light shine out from all), alluding to the Quaker concept of inner light. All Sidwell Friends students attend Quaker meeting for worship weekly.

The school's admissions process is merit-based. As documented on the school's website, it gives preference in admissions decisions to members of the Religious Society of Friends (Quakers), but otherwise does not discriminate on the basis of religion. The school accepts vouchers under the D.C. Opportunity Scholarship Program, but this program is due to be discontinued under the Omnibus Appropriations Act of 2009.