Compared to states without coverage, states with Medicaid coverage for buprenorphine had a smaller percentage of new prescribers become persistent prescribers; there was no evidence that the other state policies were associated with changes in the rate of clinicians becoming persistent prescribers. Because buprenorphine treatment is highly concentrated among a small group of clinicians, it is imperative to increase the pool of clinicians providing care to larger numbers of patients for longer periods. Greater efforts are needed to identify and support factors associated with successful persistent prescribing.