Strong epidemiological evidence exists that solar radiation is causally related to a significant proportion of cutaneous melanoma. The nature of the relationship is, however, complex and the details are not entirely clear. There appears to be a complex interplay between solar exposure in individuals with a characteristic phenotype. Although the exact quantitative and qualitative nature of this exposure is not clear, it is probable that intermittent exposures and intense exposures with consequent sunburns in a high-risk phenotype are critical in increasing the risk of developing melanoma. Despite the lack of complete understanding of this relationship, the evidence is convincing that solar radiation is causally related to cutaneous melanoma and consequently exposures to UV radiation should be reduced from early in life. The preventive measures involve reducing exposure to ambient solar radiation, by avoiding peak exposures, wearing protective outerwear, and using broad-spectrum sunscreens.