Sleet began working for Ebony magazine in 1955. Over the next 41 years, he captured photos of young Muhammad Ali, Dizzy Gillespie, Stevie Wonder, Haile Selassie, Jomo Kenyatta, former ambassador Andrew Young in a blue leather jacket and jeans in his office at the United Nations, Ghana's Kwame Nkrumah, Liberia's William Tubman and Billie Holiday. He gained the affection and esteem of many civil rights leaders, many of whom called on him by name. When Coretta Scott King found out that no African American photographers had been assigned to cover her husband's funeral service, she demanded that Sleet be a part of the press pool. If he was not, she threatened to bar all photographers from the service. Besides his photo of Coretta Scott King, he also captured grieving widow Betty Shabazz at the funeral of her husband Malcolm X. A collection of his photographs in book form, Special Moments in African-American History, 1955-1996: the Photographs of Moneta Sleet, Jr., Ebony Magazine's Pulitzer Prize Winner, was published posthumously in 1998.
