Finding out that someone with the same job description and title is making more than you can be infuriating. Even the slightest discrepancy between office mates is enough to drive down morale and divide otherwise harmonious departments. But before a serious case of salary envy propels you into your boss's office to demand more money, stay calm. Putting your paycheck on par with others requires a calculated approach.
Approach the situation as you would any salary negotiation and arm yourself with as much information as possible. Compile a detailed list of accomplishments you've made throughout the past year and include how they positively affected the company.
In this case, it's also important to have a sense of what other colleagues have accomplished. They might be making more money because their salary from another job was higher, and the company needed to match it to bring them over. It could also be that the colleague was a better negotiator and was able to eke the salary up by a few thousand dollars during the hiring process. Another reason could be that the colleague came from a different department within the company where salaries are higher, and the manager decided not to cut the person's salary to match the new department.
Either way, don't think "The Man" is out to get you, says Bill Coleman, senior vice president of compensation at Salary.com. "Have a thoughtful, prepared discussion," he says. "Spend time considering why you're not being treated fairly. You'll do a lot better if you do reasonable research about what you're good at."
You need to be bold. After gathering salary information from various sources (don't forget Web sites like Linkedin.com and Ryze.com), say something such as: "I understand from multiple sources that my colleague is being paid significantly more than me. I'd like to understand what I need to do to be paid at that level."
This is where the list of your accomplishments comes in handy. If your boss suggests things you need to do, refer to your list to see if you've accomplished them already. Also, if you have a sense that your colleague hasn't accomplished certain things suggested by the boss, feel free to point out that he or she didn't need to do that.
Peter Handal, CEO of Dale Carnegie Training, which teaches leadership skills, offers another way of approaching the topic. He suggests saying: "I've heard a rumor that people are paid more than I am. I looked at a couple of Web sites, and it's entirely possible that my salary got overlooked because the market went up. I know you don't want to have people underpaid — I know that's not the way you do business. What do we need to do to correct this?"
Your boss might try to steer the conversation toward how you figured out this information. It's important to stay as far away from that topic as possible. Let's face it: There's an office grapevine, and it's not unusual for people to discuss salary. If your manager asks how you got the information, Coleman recommends saying, "It's not important how I got the information," or "We can discuss that later. What is important is that there is a discrepancy."
Don't think that only cash is on the negotiating table. Companies are much more flexible when it comes to fringe and lifestyle benefits than they are on cash. Consider asking for paid parking, flexible hours, the ability to work from home or extra days off.
Realize that some companies have very formal salary reviews, and they can only be adjusted at certain times. If that's the case, keep notes on the conversation you had with your boss and bring it up during your review time. It's better late than never.
© 2012 Forbes.com