Cutaneous melanoma is a significant health problem throughout the developing world. Primary and secondary prevention are discussed. The wavelengths of the ultraviolet radiation spectrum and their association with melanoma are discussed. Although excessive sun exposure during childhood is a critical risk factor, excessive sun exposure during adult years is also important. The major risk factors for melanoma--numerous or atypical moles and a sun-sensitive phenotype--are genetic. Their interaction with sun exposure is currently being examined, as well as the interaction of other genetic factors, such as alterations in the melanocortin receptor and the familial melanoma gene, INK4A. Secondary prevention strategies include self-examination and physician examination. New technologies are being developed to supplement visual examination of suspected lesions. These technologies are discussed in detail and include digital photography, digital dermoscopy, confocal scanning laser microscopy and automated diagnosis systems.