Jeff Braunger, a Treasury Department official in charge of the Cuba licensing program, said in an e-mail that the department has approved licenses for 180 tour operators while making sure they are complying with the law.

"We revised the license application criteria to stress to applicants the seriousness of the requirements of the people-to-people licensing program, in part because of reports we received concerning travel under the licenses," Braunger wrote.

But some tour operators said travel to Cuba has become more cumbersome and expensive but is not policed any better. One tour organizer mentioned a recent licensed trip offered by a competitor that included a day of scuba diving.

"It's supposed to be people-to-people, not people-to-fish," the operator said.

And there are also complications on the Cuban side, tour operators said. Last month, the Cuban government abruptly canceled the landing rights for two of the U.S. charter companies operating flights to the island, reportedly over a payment dispute.

But most of the tour operators said the headaches are worth the opportunity to get in early on American tourism to Cuba, which is sure to explode when the embargo is eventually lifted.

"We are back in operations and hope to stay that way," Insight Cuba president Tom Popper said. Popper had to lay off 22 people as he waited several months for the company's license renewal, but he has since added 17 back to his staff.

On a trip organized by Insight Cuba last month, 12 Americans spent their morning speaking with Cubans at a neighborhood art project.

Michael Pettit, a lawyer from Charleston, South Carolina, said he was struck by Cuba's many contrasts during his first people-to-people trip in May.

"I love Cuba," he said. "The history, music, people, photography -- it's all beautiful."

The politics and uncertainty over continued travel between Cuba and the United States persuaded Pettit to book another trip right away, he said.

"One of the reasons I came again is because you never know when you might be able to come legally."