S.H.I.E.L.D.

S.H.I.E.L.D. is a fictional espionage, law  enforcement, and counter terrorism agency appearing in Marvel Comics. The acronym originally stood for Supreme Headquarters, International Espionage, Law enforcement Division. It was later changed to Strategic Homeland Intervention Espionage Logistics Directorate. Nick Fury is the founder of the Avengers and the head of the S.H.I.E.L.D. Black Widow and Hawkeye are direct agents of S.H.I.E.L.D. and work under Nick Fury.