The incidence of skin cancer is increasing by epidemic proportions. Basal cell cancer remains the most common skin neoplasm, and simple excision is generally curative. Squamous cell cancers may be preceded by actinic keratoses-premalignant lesions that are treated with cryotherapy, excision, curettage or topical 5-fluorouracil. While squamous cell carcinoma is usually easily cured with local excision, it may invade deeper structures and metastasize. Aggressive local growth and metastasis are common features of malignant melanoma, which accounts for 75 percent of all deaths associated with skin cancer. Early detection greatly improves the prognosis of patients with malignant melanoma. The differential diagnosis of pigmented lesions is challenging, although the ABCD and seven-point checklists are helpful in determining which pigmented lesions require excision. Sun exposure remains the most important risk factor for all skin neoplasms. Thus, patients should be taught basic "safe sun" measures: sun avoidance during peak ultraviolet-B hours; proper use of sunscreen and protective clothing; and avoidance of suntanning.