After five years on the job, you find out you're being paid only slightly more than a recently hired employee. Or you find out another co-worker with the same title, similar experience and job description is making more than you. - What should you do?
Companies can pay everyone differently, which explains why - for the most part - there is little to be gained by co-workers sharing information about what they make.
"It creates jealousy," said Douglas Branson, a professor at the University of Pittsburgh School of Law and author of The Last Male Bastion: Gender and the CEO Suite in America's Public Companies.
"People are always jealous of those who get the highest raises and make the highest incomes, which is why employers like to keep that information secret," he said.
For those who work in the public sector, the taboo on salary talk is almost moot. Everyone knows the numbers because they are public record.
There can still be hard feelings, though.
"The single biggest risk of knowing salary information, whether because it's public or a slip of confidentiality in a private company ... is poor performance," said Steve Langerud, director of career development at DePauw University in Greencastle, Ind. He said it could put a strain on relationships, cause friction in the workplace and disrupt productivity.
It might be a genuine performance issue that causes some pay disparities, and in some cases it might be helpful for the person who discovers he is making less than other co-workers to address it with his supervisor in relation to his standing and his salary for the job they do.
"At the end of the day, this could turn into a positive transparent discussion about performance, compensation and how they are related," Langerud said.
Other consultants caution that what other employees earn should be none of your business and is not relevant unless you have proof you are being discriminated against.
There are plenty of cases in which workers are not paid equally for equal work.
According to a report by the Institute for Women's Policy Research in 2009, white women had median weekly earnings that amounted to only 79 percent of what men earn. The figures are even worse for some women of color. Black women earned only 68.9 percent of white men's salaries, while Latino women earned only 60 percent.
Asian-American women on the other hand earned 92 percent of white men's salaries.
Sally Wright, president of Alliance Consulting Group in Neshanic Station, N.J., said that while discussing salaries at work may violate company policy, according to the National Labor Relations Act there is nothing legally wrong with it.
She still thinks it's usually a bad idea.
"A person who finds their salary is not as high as they think they deserve relative to others will become disenchanted, disappointed and will perform more poorly," Wright said.
"The whole system works best on the principle: Don't ask, don't tell," she said. "It's one of those cases in life - like knowing the date of your own funeral - where ignorance is bliss."