We investigate prescription drug use, and information and enrollment intentions for the new Medicare Part D drug insurance program, using a sample of Medicare-eligible subjects surveyed before open enrollment began for this program. We find that, despite the complexity of competing plans offered by private insurers under Part D, a majority of the Medicare population had information on this program and a substantial majority planned to enroll. We find that virtually all elderly, even those with no current prescription drug use, can expect to benefit from enrollment in a Part D Standard plan at the low premiums available in the current market. However, there is a significant risk that many eligible seniors, particularly low-income elderly with poor health or cognitive impairment, will make poor enrollment and plan choices.