With a Ph.D. in history and humanities from Stanford Universityand a growing body of researchChristopher Stroop initially expected to find a full-time job as a professor at an American university.

But as increasing numbers of highly qualified American Ph.D.s have discovered, you can have all the right credentials—a doctorate from a prestigious institution, fantastic references, and even a book deal—and still not secure a full-time position at an American university.

So, like many of his peers, Stroop realized that if he wanted a full-time university teaching job, he would have to leave the United States, at least temporarily. He is now a senior lecturer at the Russian Presidential Academy of National Economy and Public Administration. He’s cheerful about his location: “I love that so many friends and colleagues—so many top-notch scholars in my field—are either in Moscow, or pass through Moscow,” he says.

Stroop is indicative of a growing trend: the “passport professor.” According to a 2013 report by the Association of Governing Boards of Colleges and Universities, the percentage of tenure track positions has decreased from 78 percent of all university teaching jobs in 1969 to about 33 percent today. While some observers cheer the rise of “passport professors” who take their credentials across international boundaries, others wonder if the U.S. is witnessing an academic brain drain.

It is widely known that federal research funding cuts are spurring science Ph.D.s to look for greener pastures abroad, especially in countries with growing science funding. The National Institute of Health’s budget, for example, is about 25 percent smaller than it was 10 years ago, in inflation-adjusted dollars. In a Chronicle of Higher Education survey of more than 11,000 researchers, 36 percent expect an increase in the number of their graduating students who will seek positions abroad. And more than 20 percent say they are outright telling their students to pursue careers outside the U.S.

Alan Weber, an expert in Gulf education and an English professor at the Weill Cornell Medical College in Qatar, says the trend is clear. At least 80 percent of the faculty members at U.S. branch campuses in Education City in Qatar are American, i.e. “citizens trained in the U.S. who went abroad,” he says.

Data is beginning to show that arts, humanities, and social science Ph.D.s are following their counterparts in science and fleeing the U.S. for better opportunities overseas. For recently minted Ph.D.s in English and literature, the number of full-time university jobs in the U.S. has been in long-term decline for years. Opportunities abroad, however, seem to be on the upswing. On the Modern Language Association Job Information List, which contains job listings for full-time positions for people with Ph.D.s in English, advertisements for positions outside the U.S. and Canada have increased steadily over the past 13 years—from 35 in 2000 (about 2 percent) to 50 in 2013. The number of history Ph.D.s who went on to academic jobs in other countries has increased, too, from 7.1 percent (in the ‘02-’05 cohort) to 11.6 percent (in the ‘06-’09 cohort—the most recent data available), according to research by Robert B. Townsend, Director of the Washington Office of the American Academy of Arts and Sciences. “In more difficult job markets, it makes sense that graduates with a commitment to teaching would look elsewhere,” Townsend says.

These hard numbers only confirm what Ph.D.s have already been talking about for years. In 2010, a piece by Ph.D. student Brett Bennett encouraged history Ph.D.s to start looking for jobs abroad. “Many Ph.D.s will look to the Middle East, one of the regions of the world hiring foreign Ph.D.s.,” he wrote in in Perspectives on History, the American Historical Association’s signature publication. “Tenure is not particularly secure in this region due to political pressure and a different social system. However, the pay packages in the Middle East, and particularly in the [United Arab Emirates], are quite attractive.”

But in some cases, what seems like a solution may actually amount to career sabotage. Many passport professors are stigmatized in certain fields if they decide to return to the U.S. for academic employment. “In my field, there’s a definite sense that taking a job abroad is a sort of terminal decision,” says history Ph.D. Rachel Applebaum, a postdoctoral scholar at Tufts University. “Standard wisdom at least implies that if you work in, say, Singapore, Turkey, or Kazakhstan—all places where I’ve seen job ads in my field—you will no longer be competitive in the U.S. market.” Applebaum has also worked in Italy. She describes her job search as “never-ending and nomadic.”

David Alexander Bateman, assistant professor of government at Cornell, agrees that too much time abroad might scare a search committee at an American university. “The tenure track jobs that led many to pursue this career path are being reserved for a select few,” he says. “In such a segmented environment, the preferred jobs might be out of reach if you have had any deviation from the elite career path.”

Not everyone sees it this way, however. Ben Glaser, assistant professor of English at Yale, says three or more years abroad might be a red flag, but not necessarily a disqualification. “This year, there are four positions in all Victorian studies, for hundreds of qualified candidates,” he says. “Not recognizing the increasing diversity of career paths would be just another cruelty.” And the stigma attached to overseas teaching might be disappearing in the sciences. Michael Sheetz, a professor emeritus of cell biology at Columbia University who studies the biomedical research profession, says the quality of research in Asia is beginning to rival that of the U.S. Sheetz, now director of the Mechanobiology Institute at the National University of Singapore, says he has been able to attract “excellent” postdoctoral scholars. “The level of research abroad is increasing dramatically in China, India, and Singapore,” he says.

Back in Russia, Stroop enjoys his job, despite missing his family and worrying about international tensions. After all, he gets to immerse himself in the region he has studied for years, spend all the time he wants at the historical archives building in his neighborhood, and make a living doing what he has always wanted to do—teach, research, and write. He has even begun advising other Ph.D.s on how to go about finding employment opportunities abroad.

Correction: An earlier version of this piece stated that Rachel Applebaum had worked full-time in in Russia, Hungary, the Czech Republic, and Italy. She has only worked full-time in Italy. The piece also mis-attributed an article to Jan Goldstein; it was published by Brett Bennett. Robert B. Townsend is the director of the Washington, D.C. office of the American Academy of Arts & Sciences, not the entire Academy. We regret the errors.