Interpersonal communication for immunization capacity development is critical. Almost every study of health worker practices in the region finds that interpersonal communication for immunization overall is weak. Yet, at the same time, the vast majority of caregivers of young children cite health workers as their primary source of information about immunization. Health workers and health services must close this gap if nations and the world are to achieve universal immunization. To help strengthen the communication and community engagement skills of front-line workers1 (FLWs), the UNICEF Regional Office for Europe and Central Asia (ECARO) has developed this interactive and evidence-based training package to identify and address their own biases and misconceptions and to equip them with the essential knowledge, skills, and attitudes they need for positive and meaningful interpersonal communication.