First published in 1973, this textbook has been designed to provide medical students and other trainees with an introduction to the principles of public health with special reference to the situation in developing countries of the tropics. This thoroughly revised fourth edition focuses on recent advances in public health, retaining the approach from earlier editions in stressing basic principles illustrated by selected examples, rather than attempting to provide a detailed comprehensive account. Infectious diseases feature strongly in the textbook and are grouped epidemiologically, based on the mode of transmission and the public health approaches for their control. This fourth edition also highlights the global epidemiology of Type II diabetes and the diseases related to cigarette smoking as examples of the growing incidence of chronic diseases in developing countries. Written primarily for the developing world, the book recognises the wide diversity in the situation in developing countries and stresses basic principles that can be adapted to local situations.