Surgical complications are any deviation from the expected course of the surgical procedure. They occur as a consequence of one or more unexpected events, which can be avoided in the majority of cases through careful planning, a precise surgical technique, and correct postoperative care. Some complications, such as cardiac arrhythmias, anaphylaxis, and cardiorespiratory arrest, are life-threatening whereas others, occurring as a direct result of surgery, can affect the healing process and the final cosmetic appearance of the scar. We must therefore have not only the relevant training in dermatologic surgery, but also in basic and advanced cardiopulmonary resuscitation. In this review we discuss the perioperative measures necessary to avoid the onset of complications in dermatologic surgery and we define the various complications that can develop.