This survey found that 9 out of 10 Americans ages 50 to 64 were aware of the new health insurance Marketplace that had been created by the Affordable Care Act (ACA). The survey found that, despite widespread awareness of the Marketplace among this age group, relatively few who knew about the Marketplace were interested in using it to acquire new coverage. The survey also found that 50- to 64-year-olds' use of the Marketplace varied widely by health insurance status and income. This paper is part of a series that looks at the experiences of 50- to 64-year-olds during the ACA's first open enrollment period