A study of 1,436 Saudi children and 1,174 parents was carried out in September - October 1987 at the Children's outpatient clinic of King Faisal Hospital, Gurayat. This is the only hospital in the Gurayat town having a pediatric outpatient clinic for a population of 50,000. Of 1,436 Saudi children, 51% were male, 49% female, and 82% below five years of age. Eighty-six percent of five to 12 year old Saudi children had complete or partial immunization compared to 93% below one year of age. Only 60% of 1,174 Saudi parents knew the purpose of vaccination. Seventy percent of the fathers are educated, 34% belong to class I, II, and III and 66% to class IV and V. The main reason for delayed or no vaccination was due to sickness of the child, medical deferral, parental ignorance, and transport problem. Strict implementation of World Health Organization's (WHO) Expanded Program on Immunization (EPI) will further increase the immunization coverage as well as consolidate the success already achieved.