IT SEEMS INDICATIVE of the ubiquity of internships that this book has a cover blurb from someone for whom I once interned. Benjamin Kunkel, I recall once having to deliver something to your apartment. Benjamin Kunkel, if you are reading this, I did not feel exploited. But my pleasant summer at a literary magazine puts me in the minority of my peer group.

As Ross Perlin writes in this sharp new study, today’s teens and twenty-somethings have been taught that they must first work for free if they ever hope to get paid—and they are getting a raw deal. In what he bills as “the first book-length analysis of internships,” Perlin puts the annual value of intern labor at a conservative estimate of almost $2 billion, performed free of charge, often for companies that could probably afford a minimum-wage employee or two.

The economic and legal problems with this arrangement are glaring. Internships exclude those whose families cannot afford to support them; they displace paid workers; they allow companies to dodge liability and colleges to cash in on “internship for credit” tuition dollars. Perlin is at his best delineating the systemic flaws of an “intern nation.” It is satisfying—I say this without rage or resentment, I think—to see obvious truths forcefully articulated and persistent myths dispelled.

Perlin is generally less convincing when recounting anecdotal evidence of the intern’s dreary lot. Arduous errands and stints on clean-up duty are no fun, but as tales of workplace hardship go, they are not particularly heart-wrenching. Perlin inadvertently acknowledges this difficulty when he contrasts Western Europe’s successful intern activism with the absence of any similar movement in the United States. In our country, he writes, “the lack of a broader principled stance against contingent work, tremendous youth unemployment, and the phenomenon of ‘prolonged adolescence’ leaves internship critics sounding isolated, petty, or spoiled.” Well, yes, it does.

Still, Perlin’s point is unequivocal: “By law, there are very few situations where you can ask someone to do real work for free.” The Labor Department’s provision for unpaid on-the-job training was originally formulated for railway brakemen, and it permits periods of uncompensated learning only when certain criteria are satisfied—for example, that the work “is similar to that which would be given in a vocational school.” Few internships would satisfy such a requirement. Perlin dismisses the “convenient myth” that requiring interns to receive academic credit somehow absolves employers of responsibility to pay them. In reality, all that this “urban legend” has done is create a revenue stream for colleges, who can now receive tuition from students sitting in cubicles far off campus.