COPENHAGEN — 
As a self-employed software engineer, Thomas Sorensen broadcasts his qualifications to potential employers across Europe and the Middle East. But to the ones in his native Denmark, he is simply unavailable.
Settled in Frankfurt, where he handles computer security for a major Swiss corporation, Sorensen, 34, has no plans to return to the days of paying sky-high Danish taxes. Still, an unknowing headhunter does occasionally pass his name to Danish companies.
"When I get an e-mail from them, I either respond negatively but politely," Sorensen said. "Or I don't respond at all."
Born and trained at Denmark's expense, but working - and paying lower taxes - elsewhere in Europe, Sorensen is the stuff of nightmares for Danish companies and politicians searching for solutions to an increasingly desperate labor shortage....
Young Danes, often schooled abroad and inevitably fluent in English, are primed to quit Denmark for greener pastures. One reason is the income tax rate, which can reach 63 percent....

Denmark is the home of "flexicurity," the catchy name given to a system that pays ample unemployment and welfare benefits but, unusually in Europe, imposes almost no restrictions on hiring and firing by employers. The mixture has served Denmark well, and its economy barreled ahead in 2006 by 3.5 percent, one of the best performances in western Europe. The country is effectively at full employment.
But success has given rise to an anxious search for talent among Danish companies, and focused attention on émigrés like Sorensen. The Organization for Economic Cooperation and Development, which is based in Paris, projects that Denmark's growth rate will fall to an annual rate of slightly more than 1 percent for the five years beginning in 2009, reflecting a dwindling supply of a vital input for any economy: labor.
The problem, employers and economists believe, has a lot to do with the 63 percent marginal tax rate paid by top earners in Denmark - a level that hits anyone making more than 360,000 Danish kroner, or about $70,000. That same tax rate underpins such effective income redistribution that Denmark is the most nearly equal society in the world, in that wealth is more evenly spread than anywhere else.
The movement toward lower taxes passed Denmark by, even as it took root in much of Europe.
Small East European countries, notably Estonia and Slovakia, started the trend by imposing low, flax taxes on income and corporate profits about five years ago. Those moves helped prod Austria, and eventually, Germany, to slash high marginal rates as well.
Danish taxes also contrast sharply with those in nearby London, often jokingly referred to among Danes as a Danish town, because so many of them live there. Lower taxes on high earners have been a centerpiece of the policy mix that has fed the rise of London as a global financial center since the 1980s.
But today young Danes can easily choose not to pay for the system's upkeep, once they have siphoned off what they need. For starters, as citizens of the European Union they are entitled to work in any of the 27 EU countries.
Sorensen, who graduated from business school in Copenhagen, found himself earning the equivalent of more than $100,000 before he was 30 - and paying 63 percent of it in taxes. His work as a computer consultant for Deloitte also took him to Brussels, where he met the Spanish woman he would eventually marry.
But the high taxes, mixed with his wife's discomfort in Denmark, meant that a job offer in Qatar three years ago was all it took to pry him away from Copenhagen. Now, he is ensconced in Frankfurt, setting up a new business on the side and planning to pay no more than 25 percent of his income to the German state....