Persons preparing for careers in public health practice need a solid academic grounding in the principles of communicable disease control before arriving on the job. We have developed an introductory course in infectious disease control for the Master of Public Health program in Jerusalem, which includes instruction in the following broad areas: How do micro-organisms spread and cause disease? How do we investigate and control an outbreak? What are the basics of primary prevention by immunization and what can mass immunization accomplish? What is the importance of routine ongoing communicable disease surveillance? What are the essentials of Travel Medicine? How can public health officials provide useful information to a concerned citizenry by intelligent cooperation with the media? How can immunization programs and other programs for infectious disease control be kept current with the help of expert advisory committees? What are the best resources available to the public health practitioner in the area of infectious disease control? Armed with the essentials, the practitioner will have the tools to approach communicable disease problems in an orderly and rational way even in an atmosphere of public and professional ignorance and apprehension.