We have used the high resolution and the great depth of focus possible with the scanning electron microscope to define the surface features of normal human colon and human colonic polyps. This technique demonstrates that the surface of the normal colon has a territorialization which encompasses multiple crypts. The surface of the normal colon is covered with both absorptive cells and goblet cells. Hyperplastic polyps are covered with overdeveloped absorptive cells and the normal teritorialization is present but is distorted. Adenomatous polyps are covered with immature cells and, except for the villous adenomas, goblet cells are strikingly absent from the surface. The territorial patterns are totally obliterated in the adenomas.