The Affordable Care Act (ACA) created incentives and opportunities to redesign health care to better address mental and behavioral health needs. The integration of behavioral health and primary care is increasingly viewed as an answer to address such needs, and it is advisable that evidence-based models and interventions be implemented whenever possible with fidelity. At the same time, there are few evidence-based models, especially beyond depression and anxiety, and thus further research and evaluation is needed. Resources being allocated to adoption of models of integrated behavioral health care (IBHC) should include quality improvement, evaluation, and translational research efforts using mixed methodology to enhance the evidence base for IBHC in the context of health care reform. This paper covers six key aspects of the evidence for IBHC, consistent with mental and behavioral health elements of the ACA related to infrastructure, payments, and workforce. The evidence for major IBHC models is summarized, as well as evidence for targeted populations and conditions, education and training, information technology, implementation, and cost and sustainability.