OK, a few caveats here. First, UV-protective clothing is what you do AFTER you do sunblock. Sunblock protects the skin that isn't protected by clothing, and that's where you have the greater risk for cancer. Second, all clothing helps, and people with darker skin or people who just don't burn very easily probably don't need special clothes. Just don't be naked. Last caveat, REI is not the only place where you can buy good UV clothing. But if you want a really big selection and you want to talk to sales people trained in this stuff, you will never be disappointed at REI. Plus, their stuff looks good. If all we cared about was cancer and we never even thought about how we looked, we'd all be wearing our bedsheets to work.