A systematic study of the North American species of the section Dermocybe of Cortinarius is presented in this treatment. The taxonomy is based on a thorough study of the macroscopic features of fresh collections and a critical hyphal analysis of basidiocarps taken from these collections after they were properly dried. The author collected and described specimens of Dermocybe for over a period of seven years; four years were spent in Michigan, especially the Huron Mountains in the Upper Peninsula, one fall season in Oregon at the Cascade Head Experimental Forest, several years in California, and a brief trip to northern Idaho.