The study, which is based on data from a household level health survey conducted in 1990 in Freetown, Sierra Leone, examines the coverage of an Expanded Program on Immunization (EPI), infant mortality, and infant morbidity among children in Greater Freetown, capital of Sierra Leone. The results of the study indicate that there was a decline in infant mortality in the recent period of the survey, 1988-89, compared to earlier periods. This decline seemed to have been the result of immunization coverage, which considerably increased by 1989-90, reaching above 70% of the children under age 5. The study further reveals that the increased immunization coverage of children and their mothers might have considerably reduced the incidence of tetanus. While reduction of tetanus might have played the leading role in the latest reduction in infant mortality, the incidence of diarrhea, measles, and malaria continued to be high, suggesting that the increase in the quality and quantity of basic immunizations, oral therapy for diarrheal disease, and provision of chloroquine and improved drugs for malaria disease could further reduce most of the deaths from these prevailing diseases among children under age 5.