The Affordable Care Act (ACA), also known as Obamacare, was enacted in 2010 with the overarching goal of expanding access to affordable healthcare for Americans. It aimed to address longstanding issues within the healthcare system by implementing comprehensive reforms. The ACA sought to increase the number of Americans with health insurance coverage through measures such as the expansion of Medicaid, the establishment of health insurance marketplaces, and the provision of subsidies to make insurance more affordable. Additionally, the ACA included essential consumer protections, such as prohibiting insurance companies from denying coverage based on pre-existing conditions and allowing young adults to stay on their parents' insurance plans until the age of 26. The overarching intent was to enhance the quality of healthcare, improve preventive care, and reduce the financial burden on individuals and families facing medical expenses.The health insurance marketplaces that were created as a result of the ACA have played a crucial role in transforming the healthcare landscape in the United States. The marketplaces provide a centralized and transparent place for individuals and families to compare various health insurance plans. This accessibility makes it easier for people to find coverage that suits their needs and budget. The marketplaces also offer standardized categories of coverage, making it easier for consumers to compare plans based on essential benefits and cost-sharing structures, which simplifies the decision-making process for individuals and promotes transparency in the insurance market. The ACA also established subsidies and tax credits to make health insurance more affordable for those with lower incomes. Through the marketplaces, individuals can determine if they qualify for financial assistance, making coverage within reach for a broader segment of the population. In states that expanded Medicaid under the ACA, the marketplaces serve as a gateway for individuals with low incomes to enroll in Medicaid. This expansion has significantly increased the number of people eligible for Medicaid coverage. By creating a marketplace where various insurance providers compete for consumers, the ACA aims to promote competition, which can lead to improved quality of plans and more competitive pricing. 1 In October 2023, the Rockefeller Institute hosted the "Symposium on the Evaluation of ACA Marketplace Experience" to coincide with the tenth anniversary of open enrollment on