BACKGROUND There has been little written concerning the use of frozen sections to diagnose skin lesions. OBJECTIVE To compare the concordance between frozen and permanent sections of the same diagnostic skin biopsy specimen. METHODS AND MATERIALS Over 3 months, all non-melanocytic skin lesions that were biopsied in a skin cancer clinic were examined using frozen and permanent sections. Diagnoses from a dermatologist and dermatopathologist were recorded for each specimen and later examined for concordance. RESULTS There was rare (0.5% of specimens) disagreement recorded between interpretations of the dermatologist and dermatopathologist. Permanent and frozen section pathology agreed with one another 90.4% of the time. Specimen processing was the most probable cause of discordance. Most discordance was not clinically relevant, although the patient was clinically affected in 35 of 2009 specimens (1.7%). CONCLUSION Although there is a high concordance rate between diagnostic frozen and permanent sections, there are significant quality assurance and patient care advantages to following up initial diagnostic frozen sections with permanent sections of the same specimen.