Federal policies implemented in the last decade, including the Affordable Care Act (ACA) and the Mental Health Parity and Addiction Equity Act, have promoted insurance coverage for substance use disorders (SUDs). By providing funding for treatment services, these federal policies were intended to increase the proportion of individuals with SUDs who seek and receive evidence-based treatments. This report presents findings of a study to better understand how federal policies implemented in the past decade which promoted insurance coverage of substance use disorder treatment changed demand for treatment. In the same time period, the study looked at changes in capacity using national survey data, including new questions which were fielded with the National Survey of Substance Abuse Treatment Services on types of professionals in the field. A significant challenge still remains in increasing the demand for treatment among those with a substance use disorder or dependence, and in providing an adequate workforce.