Measurement of access to health care services is often limited to such variables as having health insurance or a usual source of care. We argue for an expanded definition of access measuring whether providers accept a particular form of insurance (overall accessibility), ease of contacting providers for appointments (contact accessibility), length of time it takes to get an appointment (appointment accessibility), and proximity of providers to patients (geographic accessibility). Interviewers posing as Medicaid beneficiaries telephoned providers in Florida's Medicaid primary care case management program, to determine whether the provider was accepting new patients, had weekend or evening hours, and how long it would take to get an appointment. Approximately 87% were accepting new patients, but only 68% were accepting new Medicaid patients. The survey also showed that beneficiaries may encounter difficulty in reaching physicians and making appointments: 22% of all calls were not answered on the first attempt and over two-thirds of providers had no weekend or evening hours.