A field trial to assess the effectiveness of a reminderrnsticker in reducing immunization dropout rates was conducted in tworndistricts of Addis Ababa between October 14, 1991 and January 31,rn1992. A total of 703 children were entered into the study. Thernstudy population was divided into intervention and control groupsrnaccording to a randomly determined schedule. The interventionrngroup received the reminder sticker and the control group did notrnrecei ve the sticker. All other services were identical. Arnbaseline interview documented the socio-demographic and maternalrncharacteristics potentially related to immunization servicesrnutilization and revealed no statistically significant differencesrnbetween the intervention and the control group. The dropout ratesrnwere 7.3% and 13.3% in the intervention and control groupsrnrespectively. The Relative Risk of being a dropout in thernintervention group was 0.55(0.35,0.87) . This difference isrnclinically and statistically (p