Most people would think twice before abandoning a high-flying executive lifestyle in Paris in exchange for an insecure, meagerly paid job in one of Europe's poorest countries. Yet this is exactly what Bozidar Djelic, a partner with consultancy McKinsey & Company, did when he accepted an offer to become Finance Minister in post-Milosevic Serbia. "I did not hesitate for a moment," Djelic recalls from his modest office in downtown Belgrade. "I have no doubt that this government can pull the country back on its feet."

After four lost wars and years of economic sanctions, Serbia needs all the help it can get. During Milosevic's rule, hundreds of thousands of bright, gifted young Serbs fled the war and the poverty to start a new life somewhere else. Djelic is one of the few who has come back. Though he looks a bit like an overgrown schoolboy in a business suit, he has had a brilliant career in France and the United States. After graduating as a top student from France's élite Institut d'Etudes Politiques de Paris, he collected two M.B.A.s from Harvard and a third from the Ecole des Hautes Etudes en Sciences Sociales in Paris. He then spent several years helping East European countries reform their economies: he advised former Russian Deputy Prime Minister Anatoly Chubais, among others, and masterminded Poland's privatization plan.

"I hope it will be a success," Djelic says of the reform movement in his own country. "But reforming Serbia is different from anything that's been done so far. So the transition plan will be tailor-made to our specific needs." Selling a market economy to Serbs may be tough. After only a few weeks in the job, Djelic is already under pressure from angry state factory workers demanding back pay and higher wages. "The former regime used to print money to pay the workers, and it led to one of the world's highest inflation rates," Djelic says. "We can't afford to repeat this mistake. I just have to tell them to be patient."

Djelic admits that it feels strange to be in back in Belgrade after more than 15 years abroad. "The city must have changed a lot, but I only see it after midnight as I leave the office," he says with a sigh. "You can't see much from a car window." Djelic's efforts may improve the view.