This spring, yoga teacher trainers in New York got to put their stress-relieving practices to the test. More than 80 yoga schools received cease-and-desist letters warning them to either obtain licenses to train teachers or risk fines of up to $50,000. The licensing process required, among other things, state approval of each school’s teacher training curriculum.

Leslie Kaminoff, founder of the nonprofit Breathing Project studio in Manhattan, responded with a July fourth “Declaration of Independence” for yoga teachers, objecting to government involvement in yoga teacher training. Kaminoff created the Independent Yoga Educators of America, a group whose mission is to protect yoga from state interference. Other teachers in New York formed Yoga for New York to fight licensing.

The efforts of the groups paid off: The State Education Department suspended its licensing push, pending action on New York senator Eric Schneiderman’s proposed legislation to change New York law so that yoga, dance, and martial arts teacher trainings would be exempt from state licensing requirements. But New York yogis aren’t the only ones feeling regulatory pressure. Yoga teacher training programs in more than 20 states have come under the watchful eye of regulators who maintain that training institutions should be licensed as vocational schools, like those that teach bus drivers.

The reasons for licensing, say regulators, are to ensure that students are giving their money to a legitimate school, that schools follow state safety guidelines, and that tuition is reimbursed if a school is unable to fulfill its promises. “The state does not want to regulate yoga,” says Patrick Sweeney, school administration consultant for the Wisconsin Educational Approval Board. “But if you’re a school, you’ve got to operate as one.”

While rules differ widely from state to state, compliance generally requires application fees (ranging from $100 in Utah to $3,000 in New Hampshire), facility inspections, surety bonds that refund tuition if the training programs go out of business, and curriculum reviews. Some teachers are complying with the requirements. Others, like Ruth Fisk and her 13-teacher collaborative, the Center for Yoga in East Lansing, Michigan, have shut down their teacher training programs.

Several programs have removed themselves from the registry maintained by Yoga Alliance, an industry group that promotes standards for yoga teachers and schools, since regulators can easily identify studios and teachers that offer teacher training programs by looking at the organization’s listings of registered yoga schools. Yoga Alliance president and CEO R. Mark Davis says that while Yoga Alliance is a nonprofit, and therefore restricted from lobbying, he talks to state regulators about their requirements and procedures, and he subscribes to a legislative monitoring service to keep up to date on actions in various states.

It’s too soon to tell how things will shake out state by state, but the current thrust toward state licensing of teacher training programs is giving rise to discussions about standards and licensing within the yoga community. And it shows that yoga is being considered big business.