RESUMEN
Managed care arrangements are the dominant form of insurance coverage in the United States today. These arrangements rely on a network of contracted providers to deliver services to their enrollees. After the managed care backlash, governments moved to ensure consumer access by issuing a number of requirements for carriers related to the composition and size of their networks and how this information is shared with consumers. The authors provide a comprehensive review of these state-based efforts to regulate provider network adequacy and provider directory accuracy for commercial insurance markets. In addition to common measures of adequacy, they also include requirements specifically targeted to underserved populations. Their assessment comes on the heels of recent empirical work that has raised significant questions about whether these efforts are effective, particularly considering the limited nature of enforcement. They also provide a brief overview and assessment of recent federal government efforts that replicate these state regulations with a focus on lessons learned from state regulations that may help improve their federal counterparts. Furthermore, they outline a future research agenda focused on a more comprehensive evaluation of efforts to ensure consumer access.