Ruthann Robson, a law professor at City University of New York and author of "Dressing Constitutionally: Hierarchy, Sexuality, and Democracy from Our Hairstyles to Our Shoes," has been tracking this issue for years in her blog, "Dressing Constitutionally." She's had plenty of disputes to write about, few that employers win. Among them: 

• An Albuquerque, N.M., hotel that would not allow a woman to work in housekeeping unless she removed her Muslim headscarf.

• A Newark, N.J., auto dealership that refused to hire a Sikh salesman unless he shaved his beard to suit the dealership dress code.

• A fast-food outlet in Laurinburg, N.C., that sought to force a Pentecostal Christian food-service employee to wear uniform pants even when her faith teaches women should only wear skirts or pants.

• A Muslim employee of a security firm fired for refusing to shave his beard.

• Seven Orthodox Jewish store owners in New York who consistently refused service to customers they felt were not dressed "modestly."

Last year, in one of the more publicized such cases, clothing chain Abercrombie & Fitch Co., agreed to pay $71,000 to two Muslim women to settle EEOC lawsuits involving their hijabs. One case involved a woman, Umme-Hani Khan, who was fired after a manager said her hijab violated the company's "Look Policy" dress code. The other suit alleged that Abercrombie refused to hire an applicant who wore a hijab.

EEOC complaints involving religious discrimination issues have more than doubled in recent years, from 1,709 filed in 1997 to 3,721 complaints filed last year.

These cases have cost employers millions. Last year, religion-based discrimination case settlements reached $11.2 million.

So, what should employers make of the EEOC's latest thoughts on religious dress?

"The guidelines are cautioning employers not to jump to conclusions that an employee's attire or grooming is not a 'sincerely held' religious belief," said Steven Anderson, an employment attorney in the Minneapolis office of Faegre Baker Daniels.  "The EEOC is warning employers that that's not their call."

Kenneth Gage, an attorney who specializes in employment issues in the Chicago office of Paul Hastings, agrees. "The agency is staking out a very aggressive position and signaling that it is willing to take on cases that push employers to respect religious diversity."

In a question-and-answer format, the EEOC guidelines present various situations an employer might encounter regarding the dress and grooming practices of employees expressing a religious belief.  Several among them:

• Does the law apply to dress or grooming practices that are religious for an applicant or employee, even if other people engage in the same practice for non-religious reasons?  (Answer: Yes)

• Can an employer exclude someone from a position because of discriminatory customer preference?  (Answer: No)

• Are applicants and employees who request religious accommodation protected from retaliation?  (Answer: Yes)

• May an employer assign an employee to a non-customer contact position because of customer preference? (Answer: No.)

• May an employer accommodate an employee's religious dress or grooming practice by offering to have the employee cover the religious attire or item while at work? (Answer: Yes, but only if the employee's religious belief permits covering the attire.)

• May an employer bar an employee's religious dress or grooming practice based on workplace safety, security, or health concerns? (Answer: Yes, but only if the practice actually poses an undue hardship on the operation of the business.)

• May an employer deny accommodation of an employee's religious dress or grooming practice based on the "image" that it seeks to convey to its customers? (Answer: Not if it is based on customer preference.)

The EEOC said in addition to accommodating an employee's dress and grooming requirements based on sincere religious belief, an employer may not segregate employees based on religion, permit harassment of employees based on religion or retaliate against an employee who requests a religious accommodation or engages in other protected activity under Title VII of the Civil Rights Act of 1964.

"There's no question the guidelines skew toward the employee," said Jonathan Segal, an employment partner at Duane Morris and frequent advisor to the Society for Human Resource Management.

Perhaps ironically, Segal expects the new guidelines to increase litigation.

"The guidelines are useful because they do heighten awareness and alert employers to the idea that you can't automatically say no to an employee who claims religious reasons for dressing or grooming in a particular way. But the guidelines don't really provide substantial help on the issues of 'undue hardship' and 'corporate image.' I think litigation may increase in those two areas when there's a clash between employer and employee."

As Robson suggested in her blog, culture clashes stemming from religious dress and grooming practices are perhaps inevitable in an America growing increasingly pluralistic. According to Department of Labor statistics, the U.S. workforce consists of about 155 million people, which includes some 25 million foreign workers.

A recent Forbes survey found that some of the most quintessentially American companies – Ernst & Young, Microsoft, Deloitte Consulting, and IBM – are among the largest employers of H-1B foreign workers, non-citizens allowed to work in the U.S. under a special visa arrangement. Foreign corporations headquartered overseas – Wipro, Infosys, Tata Consultancy, and Accenture, to name a few – also bring thousands of H-1B workers into their U.S.-based facilities.

So what should an employer do when a Vishnu tattoo pops up or a yarmulke tilts on the back of a head or a kirpin dangles from a belt loop? 

"Employers should train their managers and human resources personnel in the implementation of these guidelines," advises Faegre Baker's Anderson.

"As a practical matter," says Duane Morris's Segal, "employers should look at each situation on a case-by-case basis and see if any accommodations can be made.

As far as litigation goes, he noted that "the courts have a lower threshold than the EEOC, particularly regarding the areas of 'undue hardship' and 'corporate image.'"

In other words, employers beware.