This chapter discusses the radical surgery in late nineteenth-century America. For W. W. Keen's contemporaries his distinction between conservative and radical may have been clear enough. The classic visual representation of conservative surgery is the 1875 painting by Thomas Eakins of Samuel D. Gross, with bloody scalpel in hand, removing a piece of bone from the femur of his patient, in full view of his class of students. Samuel D. Gross gave credit for the concept of conservative surgery to Dr Philip Syng Physik, an early nineteenth-century Philadelphia surgeon. Reginald Fitz published his classic paper on appendicitis in 1886, this disorder became the typical example of the radical form of surgery. The chapter discusses the conservative, radical and heroic, each connected to a whole set of notions and traces their interconnections, and end by attempting to bring them together in the work and the thought of one of the most influential of American surgical teachers, William Stewart Halsted.