The early consensus was that the new FBI building would avoid the block-filling style of box-like architecture advocated by the General Services Administration. Staff at the NCPC advocated an aggregation of smaller, interconnected buildings, while President's Council on Pennsylvania Avenue architectural consultant Nathaniel A. Owings suggested that small retail shops be incorporated into the ground floor of the building. Staff at the President's Council on Pennsylvania Avenue said the council would "blow its top" if the FBI headquarters design was monolithic.