NEW YORK ( MainStreet) — When is a labor union not a labor union? If it walks like a labor union, talks like a labor union, then it must be a labor union - right?

Not necessarily. There is a new organized labor model in town and it is not your father's labor union. A new type of labor union - for a new generation - came into being back in the late 1970s and early 1980s, and they are gaining prominence today.

These alternative labor or "alt-labor" organizations take various forms. Often they are known as "worker centers" or "workers' alliances." But they could also be unions that do not have collective bargaining rights. Another model would be an organization of independent contractors who are not covered by the National Labor Relations Act. The Freelancers Union in New York City is such a group.

They were spawned by immigrant worker movements. Related to civil rights organizations at that time these alt-labor groups provided help to low wage workers.

One of the earliest centers was in a border town in El Paso, Texas that was established for low wage women garment workers, explained Janice R. Fine, an associate professor of labor studies at Rutgers University and author of Worker Centers: Organizing Communities at the Edge of the Dream .

Fine noted the growth of these organizations just during the last 20 years.

"By 1992 there were five, by 2005 there were 155 and now there are 215," she said. "They tend to be among immigrant communities. They do a combination of service, advocacy and organizing."

According to Fine, these organizations are, for the most part, funded by community based foundations. Some examples of these that she cited were the New Jersey Unitarian Universalist Reach Program; the Public Welfare Fund; and the Ford, Rockefeller, ARCA and Carnegie Foundations.

Whatever their relationship was to the civil rights movement in the past, these new models are now necessitated by the fact that union membership is dwindling - and interest in joining unions by younger workers is dwindling even more.

So how does this affect younger workers?

"Honestly it's hard to predict since it's a relatively new phenomenon," said Patrick Semmens, a labor lawyer and vice president of the National Right to Work Foundation, an organization advocating right-to-work laws.

"So far many of the alt-Labor organizations seem to be just front groups for early-stage union organizing," he continued.

But Fine thinks that these groups are providing a public service. She rejects the criticisms as being unfounded.

"They are not front groups for organized labor," she said. "That is a spurious claim. They are not being usurped by organized labor. They created their own national organizations. The vast majority did not have a relations with unions. Now some are working more closely with unions and that is a good thing."