From 1903 to 1919, he served as president of the American Negro Academy, the leading intellectual organization for African Americans. After 1913 he devoted himself to the National Association for the Advancement of Colored People (NAACP), serving until 1923 on its national board. Through 1924 he also served as president of the District of Columbia branch, becoming a key figure in the NAACP’s efforts to oppose racial discrimination at the federal level.