WASHINGTON (AP) -- Thousands of part-time college professors are joining labor unions, a growing trend in higher education that's boosting the ranks of organized labor and giving voice to teachers who complain about low pay and a lack of job security at some of the nation's top universities.
The move to unionize at campuses from Georgetown University in Washington, D.C., to Tufts University near Boston follows a shift in hiring practices at colleges that rely more than ever on adjunct faculty to teach classes.
Last month, adjuncts at Tufts became the latest to join the 2.1 million-member Service Employees International Union, which has been aggressively targeting college instructors. Adjuncts at Georgetown formed a union with SEIU in May, and part-time instructors at nearby American University joined the union last year.
SEIU now represents more than 18,000 members at 10 colleges and universities, compared with 14,000 five years ago. The union is preparing to file for elections at more colleges in the Los Angeles, Seattle and Boston areas.
Adjunct professors now make up more than half of all college faculty nationwide; in the 1970s, about 70 percent of college instructors were tenured professors or on a track to tenure.
Unlike full professors, most adjuncts earn just a few thousand dollars per class, with scant benefits and little job security.
"What started out decades ago as a way to supplement experience on college campuses by using adjunct professors has flipped," said Malini Cadambi, SEIU's national director of higher education. "They are the majority of faculty labor on many campuses now, and their position has not improved."
Kip Lornell, an adjunct music professor at George Washington University in the District of Columbia, has been teaching students for 25 years and is the author of 13 books on American music. He earns less than $23,000 a year teaching three classes at GWU. By contrast, a full professor at the university earns an average salary of $156,000 a year, according to data compiled by the American Association of University Professors.
Lornell says conditions have improved since GWU adjuncts formed a union in 2006 and won a contract two years later. Salaries are 20 percent higher, and the university now pays minimum rates of $3,500 or $4,030, per 3-credit course, depending on the lecturer's degree. The university also now has to go through certain procedures before deciding not to bring an instructor back.
"There's no question it's because of the union contract," Lornell said.
Higher education has been a rare bright spot in labor organizing in recent years as union membership has dwindled to 11.3 percent of the overall workforce and 6.6 percent in the private sector.
The American Federation of Teachers has added more than 50,000 new members in higher education since 2000. The majority of that growth has come in "contingent faculty," a category that includes part-time adjuncts, graduate assistants and full-time nontenured faculty.
"We've identified this as one area we're going to put significant resources into," said Craig Smith, AFT's director of higher education.
Unions say they are not seeing quite as much pushback from colleges as they do in many private-sector union campaigns.
At Georgetown, administrators at the Jesuit university decided to take a neutral position on the union vote. But there was more resistance at Bentley University in Boston, where SEIU lost a unionization vote this month, 100-98.
"We made it clear in our statement and in communications with faculty that we do not feel it is necessary to unionize," Bentley spokeswoman Michele Walsh said. "We encouraged those faculty who agreed with this stance to vote accordingly."
Universities used to call on adjunct professors in mostly technical fields such as allied health, journalism or business to bring students more practical training. Many adjuncts still have full-time jobs and teach a class on the side. But as tenure-track positions decline, those who want to make teaching a full-time career have to cobble together jobs at multiple colleges and universities to make ends meet.
Colleges are relying more on adjuncts to teach basic classes as cash-strapped state governments have reduced funding for public universities, said Adrianna Kezar, a professor of education at the University of Southern California who studies the role of adjunct faculty.
Private universities also are under pressure to keep skyrocketing tuition levels down. Universities like the flexibility that adjuncts offer to deal with the uncertainty of predicting student enrollment.
A recent study showing median pay per course is about 25 percent higher on campuses where adjuncts have union representation. The report last year from the Coalition on the Academic Workforce, an advocacy group that seeks better working conditions for part-time faculty, found that median pay nationwide for teaching a standard three-credit course was about $2,700.