Everything seemed set for the American debut last month of Pitingo, the rising young flamenco singing star: the Grand Ballroom at Manhattan Center had been booked, tickets and program prepared, a publicity budget spent, nonrefundable airline tickets purchased. But when he went to the United States Embassy in Madrid to pick up his visa, he learned that his name was on the “no fly” list.

Embassy officials knew that Pitingo, whose real name is Antonio Manuel Álvarez Vélez, is not a terrorist, and that the real target was someone else who shared his very common name. But procedures are procedures, and by the time the confusion was sorted out it was too late for Pitingo to fly to New York, and his concert had to be canceled. His management and the concert promoters incurred losses of nearly $25,000.

The case of Mr. Álvarez is not an isolated one. In the decade since the attacks on the twin towers, American visa procedures for foreign artists and performers have grown increasingly labyrinthine, expensive and arbitrary, arts presenters and immigration lawyers say, making the system a serious impediment to cultural exchanges with the rest of the world.

Some foreign performers and ensembles, like the Hallé orchestra from Britain, have decided that it is no longer worth their while to play in the United States. Others have been turned down flat, including a pair of bands invited to perform at the South by Southwest festival in Austin, Tex., last month, or have ended up canceling performances because of processing delays, as was the case last month with the Tantehorse theater troupe from the Czech Republic, which was booked to perform in suburban Washington.