Jennifer J. Isler, best known as J. J. Isler and also known by her maiden name of J. J. Fetter, is an American yachtswoman from San Diego, California, United States. She is a two-time Olympic medalist and a world sailing champion. She was a starting helmsman in the 1995 America’s Cup races. A pioneer in the sport of women’s sailing, she was the first woman inducted into the Sailing World Hall of Fame.
She was born into a sailing family, the youngest of three children of Jane and Tom Fetter; he is a former commodore of the San Diego Yacht Club. She began sailing Sabots when she was 7 years old. She learned to sail and race in the Juniors program at the San Diego Yacht Club, sailing mostly in Sabots. An intense competitor, she disliked the fact that girls and boys were viewed differently in sailing. "The junior regattas were open to everyone, but there was a winner's trophy and a 'first girls' trophy," she recalled recently. “I always wanted just to be first, and hand that other trophy off as 'the first boy trophy’. … I finished second, third and fourth in the Sabot Nationals, but never won, meaning I was always getting that 'first girl' trophy, and I hated it."