An increasing focus on the prevention of medical errors is a direct result of a growing patient safety movement. Although the reduction of technical errors has been the focus of most interventions, cognitive errors, usually more than one error linked together, actually cause the majority of misdiagnoses. This article examines the most common types of cognitive errors in dermatology. Two methods to minimize these errors are recommended: first, cognitive debiasing techniques reduce the common initiating factor of error cascades; and secondly, the application of prospective hindsight attacks the final common pathway that leads to misdiagnosis.