The American progressive architectural practice most widely known as Purcell & Elmslie (P&E) was the second most commissioned firm of the Prairie School after Frank Lloyd Wright. The firm had offices in Chicago, Philadelphia, and Minneapolis.The firms consisted of three partnerships: Purcell and Feick (1907–10); Purcell, Feick, and Elmslie (1910–12), and Purcell and Elmslie (1913–21).