There is an increasing interest in the etiology of cutaneous malignant melanoma (CMM). Once considered a rare tumour, CMM is now the fourth commonest cancer in Australia and New Zeland, the tenth in the Usa, Canada and Scandinavia and the eighteenth in Great Britain. The growing scientific concern on the urgent need to highlight the cause/s of CMM is well documented by the large number of well-designed and well-conducted epidemiological studies reported in the last two decades. Such studies facilitated testing of many etiological hypotheses derived from earlier descriptive investigations and contributed to significant progress in understanding the etiology of such disease. The quantification of the extent to which the increases in CMM incidence and mortality rates are related to new lifestyles and to new patterns of exposure to potential carcinogenetic agents is essential in order to establish an appropriate preventive strategy. In population of mainly European origin a substantial proportion of the increased incidence of CMM is attributable to steady change from predominantly occupational to predominantly recreational exposure to solar radiation. Therefore the present review puts particular emphasis on exposure to sunlight as well as to artificial ultraviolet light, as modifiable causes of CMM. Incidence and mortality data and other potential risk factors for the development of CMM will also be briefly reviewed.