The primary goals of the Affordable Care Act (ACA) were to increase the availability and affordability of health insurance coverage and thereby improve access to needed health care services. Numerous studies have overwhelmingly confirmed that the law has reduced uninsurance and improved affordability of coverage and care for millions of Americans. Not everyone believed that the ACA would lead to positive outcomes, however. Critics raised numerous concerns in the years leading up to the law's passage and full implementation, including about its consequences for national health spending, labor supply, employer health insurance markets, provider capacity, and overall population health. This article considers five frequently heard worst-case scenarios related to the ACA and provides research evidence that these fears did not come to pass.