At first glance, the typical surfer dude might not seem to be the most obvious candidate to deserve the label "environmental advocate." But wait until you meet the members of the Surfrider Foundation. An international organization of hard-core surfer-environmentalists, Surfrider has 25,000 members in seven countries. Glenn Henning, one of the organization's founders, sums up the philosophy on which Surfrider was built: "No surfer in the world can be a surfer without first being an environmentalist." Now pushing 50, Glenn took a hard look at the surf scene about 15 years ago and didn't like what he saw. Join National Geographic and see how Glenn started "making waves" to draw attention to the plight of oceans, reefs, and beaches.