Many serious communicable diseases are easily preventable by immunization. The World Health Organization estimates that it saves between 2 to 3 million lives every year – the majority in regions with low incomes, under-developed infrastructure and large rural populations. Immunization (vaccination) can make an enormous difference to the health of individuals, communities, and nations like Ethiopia. The vaccine-preventable diseases currently included in the National Expanded Programme on Immunization (EPI) in Ethiopia are tuberculosis, poliomyelitis, diphtheria, pertussis (whooping cough), tetanus, measles, pneumonia and meningitis due to Haemophilus influenzae type b, and hepatitis B disease. The ten study sessions in this Module contain clear guidelines on how to conduct all important immunization activities. Much of the credit for successful immunization campaigns is due to the activities of health professionals like you. This is why you have such a big part to play in protecting women and children from vaccine-preventable diseases in your community. We hope that this Module will help you in this effort.