Knowledge is power. It's also one of the most important tools you have when negotiating your compensation plan after you receive a job offer. While there are many factors that come into play in the negotiation process -- benefits, perks and work-life balance -- salary is one of the trickiest things to get right, says Rick Gillis, job search expert, career strategist, consultant and author.What Are You Worth?One of the most important things to understand is your worth in the current job market, says Gillis. That also means having an understanding of current market conditions and economic outlook, he says, regardless of your past compensation.[Related: How to Attract and Retain Talent by Using Compensation Benchmarking]"You have to understand and accept that the market rate may not be what you're currently making," Gillis says. "If you're making $100,000, for instance, but the economy has tanked in your area, then you're just not worth that much anymore, and you won't be able to command that much," he says.Gillis says keeping up with the Bureau of Labor Statistics salary data is a great place to start, even though the data published can be anywhere from 30 to 45 days old. Beyond knowing your current market value, Gillis says, communicating to your potential employer that you're aware of and accept the reality of the economic situation can help ease the negotiation process."Going into negotiations armed with this data says to the employer, 'I understand the current market and I'm willing to negotiate based on your rate,'" he says. But that understanding must go both ways, and compensation data can also help justify to an employer why you're worth the salary you've requested.Selling Your Value"Real-time market data on compensation is crucial because you can back up your assertions with fact," says Katie Bardaro, lead economist with compensation data and services provider PayScale. "You can use that data to help sell yourself and your skills to the employer; hammer home why you are a good value for the money, and what skills and knowledge you will bring to the company," Bardaro says.[Related: Better Compensation Key to Retaining Top Talent]It's important to remember, too, that employers will begin negotiating at the bottom of their approved salary range and deliberately leave room for some negotiation, Bardaro says. "If their offer matches what you've discovered in your own research, great. And if they can't meet your requirements, remember that there are many types of non-salary compensation to consider," Bardaro says.Consider Factors Other Than Salary"Whenever an offer is made, there's most likely a $5,000 to $10,000 'buffer' that you can get without the hiring manager or HR person having to get additional approval," says Gillis. Besides the obvious benefit of gaining a higher salary, your negotiating skills and the respect you'll earn from standing your ground is a powerful thing, Gillis says."I advise my clients to always negotiate, even a little, if they think it's appropriate," Gillis says. "They can always go back and say, 'On further consideration, I do accept your offer,' but the respect and admiration they'll get is something that will stick with the employer," he says.Of course, negotiating and salary and negotiating the whole of a job offer aren't one and the same, as Professor Deepak Malhotra says in this article for the Harvard Business Review. (You can also check out Professor Malhotra's video presentation that he makes to students.) But unfortunately, many job seekers believe negotiating salary and negotiating a job offer are synonymous."Much of your satisfaction from the job will come from other factors you can negotiate," says Malhotra in the article, "Perhaps even more easily than salary," he says, and Bardaro adds that focusing a negotiation solely on salary might send the wrong impression to employers."If you make it all about the money, your potential employer's going to wonder what your true motivations are," says Payscale's Bardaro. "Are you actually going to care about the future and success of the company as a whole? Are you going to work hard to contribute to growth and development of the business? That's why you also should focus on other types of benefits," she says. Those other benefits can be things like vacation time, flexible work arrangements, child care, tuition reimbursement and so on.A potential employer considers your salary their monetary investment in a business asset -- you, says Gillis. If you're focused only on the financial benefits, they'll begin to wonder how sound their investment is; it's important to help them understand your total business value, he says."If you can't get the salary you want up front, see if you can negotiate a salary review in six months," says Gillis. "In that six months, you need to focus on kicking butt and delivering over and above what's expected of you to prove you're worth the salary increase," he says. Get any agreement like this in writing, and make sure you're documenting and quantifying your contributions to demonstrate your value, he says. \n\nYou also can ask for a better title or perks like more vacation time, paid parking or commuting expenses, memberships to professional organizations or trade associations, relocation expenses -- get creative, says Gillis. This can signal to your employer that you are not only invested in working for them, but are a great problem-solver and are willing to persevere even if conditions are not ideal.Finally, remember to smile, Gillis says. While negotiations can seem confrontational, the goal is to come to a common, mutually beneficial understanding, he says."The employer's job is to get the best talent for the least amount of money. Your job is exactly the opposite," Gillis says. "When it comes down to it, you're both people, and the goal is to reach a common ground. The company's made you an offer already, so they want you to work for them, and they're hopeful you'll want to work for them, too. You just have to make it a win for both sides," he says.Sharon Florentine covers IT careers and data center topics for CIO.com. Follow Sharon on Twitter @MyShar0na. Email her at email@example.com Follow everything from CIO.com on Twitter @CIOonline and on Facebook.