Don't quit right away in anger, especially if you don't have another job offer in hand. Take time to think about why you were denied a raise, and whether it's worth sticking around. If, for instance, the company is in a dire financial situation and you don't think it will improve any time soon, it may be time to launch a serious job search. But otherwise, you may want to see if you can improve your chances for a raise at a later date.