Evidence from randomized controlled trials demonstrated that regular sunscreen use prevents cutaneous squamous cell carcinoma.1-3 Until now, there were no randomized controlled trial data on the effects of sunscreen use in melanoma prevention, and case-control studies yielded conflicting results.4,5 The community-based skin cancer prevention trial conducted by Green et al6 in the subtropical region of Nambour, Queensland, Australia, provided evidence from a randomized controlled trial that regular use of sunscreen prevents melanoma. The study included 1621 adults randomized to regular sunscreen use or to discretionary use, which included no use at all. Those randomized to regular sunscreen use were given an unlimited supply of broad-spectrum sunscreen with a sun protection factor (SPF) of 16 and asked to apply it to the head, neck, arms, and hands every morning. Reapplication was advised after heavy sweating, bathing, or long sun exposure.