Yale’s Sociology Department has continued its rebuilding effort by hiring two top international scholars, one at the senior level and one at the junior level.

Karl Ulrich Mayer, the director of the Max Planck Institute for Human Development in Berlin, will fill a senior slot, and Philip Smith will leave his tenured position at Australia’s University of Queensland to join Yale’s faculty as a junior professor.

Sociology chairman Ivan Szelenyi called the senior appointment a coup for Yale but said the junior appointment came after the department’s first four choices for the position accepted offers at other American universities.

Szelenyi, who is currently on a leave of absence at the Max Planck Institute, said a rebuilding department must try harder to recruit talent “the competition has not spotted yet.”

“This is really something extraordinary,” Szelenyi said. “In a department which is rebuilding, we have to be entrepreneurial and find talent outside the United States.”

Szelenyi said hiring someone like Mayer will not only fill a hole in Yale Sociology’s offerings but also raise the department’s profile.

“Getting someone from the Max Planck Institute is considered next to impossible,” Szelenyi said.

In addition to teaching at both the graduate and undergraduate levels, Mayer will head the new Center for Quantitative Social Science Research when he arrives on campus next January.

Jeffrey Alexander, the acting chairman of the Sociology Department, praised Smith, an expert in legal studies and criminal justice.

“He’s probably the best-known young sociologist in Australia,” Alexander said. “So for him to give up a secure job to take part in the rebuilding process says a lot.”

Neither Mayer nor Smith was available for comment.

The two appointments come as another step in the department’s massive rebuilding initiative. After a decade marked by retirements, departures and the near elimination of the department, Yale sociology began rebuilding under Szelenyi and sociology professor and former chairwoman Deborah Davis.

But Yale College Dean Richard Brodhead said that even rebuilding departments aim only to attract top-notch faculty.

“If you want to rebuild a department that has lots of difficulties, there’s a temptation to go after people who are likely to come,” Brodhead said. “But in the long run, that’s not the best option. You want to get first-class people.”

Szelenyi said Yale might have been appealing to Mayer because his new position will allow him to concentrate on research and teaching. At the Max Planck institute, where Mayer has been the director for nearly two decades, Mayer has focused on administrative tasks.

“He has been doing a lot of work facilitating research for a lot of other people,” Szelenyi said. “So I think at this point in his life, the opportunity for him to concentrate on his own research and teaching is appealing.”

Szelenyi said Smith, whom many consider one of the top sociologists in Australia, will come to Yale hoping to establish himself in the United States.

“Having been in Australia, he did not have quite the impact that he could’ve had he been at a major American university,” Szelenyi said. “He wants to make a mark on the profession, and this is exactly what Yale expects of him.”

Although Smith has a senior position at the University of Queensland, he will be a junior professor at Yale because of differences in tenure standards.

Szelenyi said Smith was hired after four other junior-level offers fell through this year. Those candidates, whom Szelenyi called “the top people on the market,” accepted offers at Columbia University, Northwestern University, the University of Wisconsin, and the University of California at Berkeley.

The department still has three more senior offers pending, for one of which Szelenyi said there is little hope.

“If we could get one more acceptance this year, I would be very, very happy,” Szelenyi said.