In this study, subjects will be randomly assigned (by chance, like the flipping of a coin) to one of two study groups. Half the subjects will be assigned to a training program, which will consist of 8 sessions over a period of 8 weeks in which they will be instructed in cognitive therapy ( a method of identifying and "talk back" to one's negative thoughts) and a variety of other stress-reducing techniques. The other half will be assigned to a control groups, which will no receive instruction in cognitive therapy or the other stress-reducing techniques. All subjects, both those in the training program and in the control group, will receive the usual care for hepatitis C that all patients in the Hepatology Clinic receive. All subjects will also be asked to participate in 6 testing visits over the course of the study. The first testing visit will last about 3 hours, which the others will last between 1 1/2 and 2 hours. Subjects will alo be interviewed by telephone about their personal and family medical and psychiatric history. This will take about an hour.