Leech therapy is experiencing a resurgence in health care today, primarily in plastic and reconstructive surgery as a treatment for venous congestion, which can threaten surgical outcomes. Most nurses have had no formal training in administering the therapy or in maintaining Hirudo medicinalis, the species of freshwater worm used therapeutically. Yet nurses may be expected to participate in this therapy in a variety of clinical settings and can use these guidelines for the safe and effective use of the leech in treatment.