BACKGROUNDUndermining and hemostasis are basic surgical techniques that can have a significant impact on surgical outcomes. OBJECTIVETo review the mechanisms and techniques of undermining and hemostasis, with an emphasis on the advantages and limitations of each modality. MATERIALS AND METHODSThe PubMed database was searched for articles with the keywords “undermining,” “hemostasis,” and “electrosurgery.” RESULTSWhether performing blunt, sharp, or electrosurgical techniques, undermining at the appropriate depth and width is necessary for tissue movement during closures. Both excessive and inadequate undermining can compromise surgical healing. Surgical hemostasis techniques include pressure, suture ligation, topical hemostatic agents, and electrosurgery. Dermatologic surgeons should select the appropriate amount and type of hemostasis for each procedure. Particular care should be taken in performing electrosurgery, given the potential for complications. CONCLUSIONUnderstanding and optimizing hemostasis and undermining will allow dermatologic surgeons to execute complex closures with minimal complications.