Henry Sears came from a long line of New England seafaring men. His grandfather, David Sears, Jr., joined the New York Yacht Club in 1844, the year of its founding. Sears studied oceanography at Yale and worked at the Woods Hole Oceanographic Institute before moving to New York in 1936. His sailing career began in the Marblehead Brutal Beast Class. Later, he raced an Alden O-Boat. In his youth. Sears crewed with such legends as Charles Francis Adams and Charles P. Curtis aboard a succession of R-Boats, Q-Boats, and German built Sonder Boats. He started cruising aboard his Alden Cutter, ACTAEA, in the 1920's and in 1936 built the Paine 36, ACTAEA, that he sailed to finish third overall in that year's stormy Bermuda race.
In 1956, after a nineteen-year hiatus in America's Cup racing, Sears, as Commodore of the New York Yacht Club, appealed to the Supreme Court of New York to amend the Cup's Deed of gift. Greatly increased building and operation costs, plus a shortage of qualified hands, had virtually prohibited continuation of J-Class racing. Harry Sears' action resurrected the competition in smaller, more practical yachts, the 12-Meters. Commodore Sears then served as syndicate head and navigator of the 1958 Cup Defender, COLUMBIA. His leadership ushered in a new era of fine racing for the America's Cup that continues to this day, thanks entirely to the action of Commodore Sears.