This study proposes to use functional magnetic resonance imaging (FMRI) to observe brain activity and behavior associated with decision-making about rewards (DD task), working memory and working memory cognitive persistence (WM task), and craving (CR task) in 72 opiate dependent participants initiating buprenorphine. While stably using opiates (initial study appointment) and again during withdrawal (approximately 3 days later), participants will receive an FMRI scan with behavioral challenges; immediately after the second FMRI, they will receive their first dose of buprenorphine. Buprenorphine treatment will continue for twelve weeks, followed by a four week taper. Urine toxicological analysis will be performed prior to the first scanning session, weekly for two weeks and biweekly thereafter.