This final rule increases access to medication-assisted treatment (MAT) with buprenorphine and the combination buprenorphine/naloxone (hereinafter referred to as buprenorphine) in the office-based setting as authorized under the United States Code. Section 303(g)(2) of the Controlled Substances Act (CSA) allows individual practitioners to dispense or prescribe Schedule III, IV, or V controlled substances that have been approved by the Food and Drug Administration (FDA). Section 303(g)(2)(B)(iii) of the CSA allows qualified practitioners who file an initial notification of intent (NOI) to treat a maximum of 30 patients at a time. After 1 year, the practitioner may file a second NOI indicating his/her intent to treat up to 100 patients at a time. This final rule will expand access to MAT by allowing eligible practitioners to request approval to treat up to 275 patients under section 303(g)(2) of the CSA. The final rule also includes requirements to ensure that patients receive the full array of services that comprise evidence-based MAT and minimize the risk that the medications provided for treatment are misused or diverted.