Chad Nelsen grew up where the land runs out — raised on the beaches of southern California, working as a lifeguard before turning his eye toward coastal science and eventually to the fight to save the shores that shaped him. As CEO of the Surfrider Foundation, he now leads one of the ocean's most tenacious grassroots defenders: a 50,000-member coalition of surfers and saltwater devotees waging campaigns on fronts that range from protecting surf breaks to pushing back against plastic pollution, climate disruption, and the long-standing barriers that have kept the ocean's culture from being as open as the sea itself. In a moment when the tide seems to be running the wrong way, Nelsen holds to a conviction that bottom-up pressure — the kind that starts with people who simply love the water — can still change the course of things.