After seeing Blue Crush a few years ago, I signed up for surf camp. Friends (male and female alike) laughed when they heard. Surfing is hard, they said. Even for guys, was the unspoken part.

Apparently, no one told that to Izzy and Coco Tihanyi, the 32-year-old twins who founded Surf Diva, the camp -- taught for girls, by girls -- that I signed up for. The sisters set up shop in 1996 with $328 and Izzy's surfboard collection. Guys who surfed the same beach heckled their classes and sometimes cut in front of their students. "They thought they had some sort of claim to the ocean," says Izzy (above, right).

But the sisters kept at it, and the business grew. Today, Surf Diva's 50 instructors teach thousands of people to surf each year. Half of all revenue comes from sales of Surf Diva fashions sold at a company-owned boutique and by 50 retailers in the U.S., Japan, and England.

All is not well in the surf-camp world, however. State beaches have begun asking camps for as much as 20% of gross revenue in exchange for the correct permits; cities want up to 10%.

To defend their surf turf, the Tihanyis set up an industry group to lobby officials. "Can the city really enforce this kind of restriction of use of the ocean," Izzy asks, "and can they really force us to open our books to them and just take a percentage like that?" My money's on the divas in this fight. After all, it's their world. We just surf in it.

Alison Overholt