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In 2008, the National Association of Colleges and Employers found that 83 percent of graduating students had held internships, up from 9 percent in 1992. This means hundreds of thousands of students hold internships each year; some experts estimate that one-fourth to one-half are unpaid.
In California, officials have issued guidance letters advising employers whether they are breaking the law, while Oregon regulators have unearthed numerous abuses...
...Of course, many internships — paid or unpaid — serve as valuable steppingstones that help young people land future jobs. “Internships have become the gateway into the white-collar work force,” said Ross Perlin, a Stanford graduate and onetime unpaid intern who is writing a book on the subject. “Employers increasingly want experience for entry-level jobs, and many students see the only way to get that is through unpaid internships.”