Congress has seen a renewed interest in the market for private health insurance since the passage of the Patient Protection and Affordable Care Act (ACA). This book provides an overview of private-sector (as opposed to government-provided) health insurance. It serves as an introduction to health insurance from the point of view of many consumers under the age of 65. Furthermore, the book provides background information about modifying or building on the current health insurance system; discusses how understanding the potential impact of such proposals requires a working knowledge of how health insurance is provided, purchased, and regulated; and describes various ACA provisions that affect the private insurance market.