The aim of this study was to determine the impact of reminder systems on appointment nonadherence rates in an low-income inner-city clinic population. A total of 2,304 consenting patients were randomly assigned to one of three groups: (1) automated telephone reminder, (2) postcard reminder, or (3) no reminder. In contrast with research on other populations, the results of this study demonstrated no significant difference in appointment adherence rates among the three groups. To aid in the development of more effective interventions in the future, individuals not attending their scheduled appointments were interviewed by telephone to determine reason for nonadherence.