The determinants of realized, perceived, and potential access to prescription drugs among an elderly population were studied. Data were derived from telephone interviews of 3498 noninstitutionalized elderly persons living in west Texas. Access indicators examined were whether the respondents were taking prescription drugs, had perceived problems in obtaining prescription drugs, had comprehensive prescription drug insurance, and had a usual pharmacy. On the basis of the behavioral model of health services, multivariate logistic regression analysis was performed to determine whether predisposing, enabling, and need factors were associated with each access indicator. Approximately 14% of the patients were not taking prescription drugs at the time of the interview. Of the patients who were taking prescription drugs, about 16% reported having problems obtaining prescription drugs and 24% primarily used a single pharmacy. Nearly 36% did not have comprehensive prescription drug coverage. Among the four indicators of prescription drug access, lack of prescription drug insurance was the most prevalent barrier. Employer-provided insurance improved access more than any other type of coverage. Elderly consumers taking more medications reported more problems accessing prescriptions than those taking fewer medications. Among the indicators of access to prescription drugs among noninstitutionalized elderly people in west Texas, lack of prescription drug insurance was the most prevalent barrier.