Signed by President Obama on March 23, 2010, the Affordable Care Act (ACA) included provisions to expand health coverage to eligible Americans, control health care costs, and improve the health care delivery system. The ACA closed the Medicare Part D donut hole/coverage gap and expanded coverage of preventive services for people with Medicare. The Act also created state-specific Marketplaces, where individuals can go to purchase health insurance. Generally, people who are eligible for Medicare should not buy health insurance in the Marketplace.