Acne is a common condition experienced by up to 80% of people between 11 and 30 years of age and by up to 5% of older adults. In some patients, the severe inflammatory response to Propionibacterium acnes results in permanent, disfiguring scars. Over the past several decades, numerous descriptive terms and surgical techniques have been used to diagnose the types, and improve the appearance, of scarring in those persons with acne. We propose a descriptive, simple, universally applicable acne scar classification system that includes 3 scar types: icepick, rolling, and boxcar. We also have developed an effective treatment algorithm for reconstructing and improving the appearance of acne scars including punch excision, punch elevation, subcutaneous incision (Subcision), and laser skin resurfacing. This new classification system for acne scars enables the physician to more precisely identify scar subtypes. Once the scar type has been defined, appropriate and effective treatment protocols can be developed. (J Am Acad Dermatol 2001;45:109-17.)