Reasons for quitting gambling were reported by two samples of problem gamblers, long-term quitters and recent quitters, using two methodologies. The participants first described their reasons for quitting in an open-ended fashion and then with a 15-item checklist. There was a fair degree of similarity between the responses of the two samples. Both groups most frequently reported that their resolution was a conscious decision, although recent quitters were more likely to report that the decision evolved over a long period of time vs. being an immediate decision. About a third of both groups described their decision as related to a specific event and involving a crisis. In both methods, negative emotions and financial concerns were most often reported. The checklist method yielded about three times as many reasons as the open-ended method. There were no gender differences in reasons although participants with a treatment history reported more reasons than those who had not sought treatment.