This is the first ever such atlas to be produced for I ndian farmers and poultry professionals. Its objective is to provide a handy tool to farmers for on-the-spot diagnosis of diseases, under field conditions. Although a large number of laboratory tests, some sophisticated like ELISA and per, have been developed for the diagnosis of poultry diseases, they are either not available or are beyond the reach of most farmers. Moreover, by the time birds reach laboratory, they are mostly decomposed and unfit for postmortem examination and disease diagnosis. The delay in diagnosis allows the disease to inflict mortality and ruin farmer`s economy. The key to disease control then is on-the-spot diagnosis. It is with this objective that the colour atlas has been produced - to make readily available to poultry farmers a handy tool for immediate and accurate disease diagnosis under field conditions. A large number of poultry diseases, including the more deadly like Ranikhet and Gumboro, leave their footprints in the dead bird. From these characteristic postmortem findings, it is possible to arrive at a correct diagnosis. The atlas provides 150 coloured photographs and covers a wide spectrum of poultry diseases. For important diseases, several photographs are given so that at no stage their diagnosis is missed. Also, wherever considered appropriate, pictures of live birds showing symptoms of specific diseases are given. In addition, each disease is accompanied by a brief description that highlights its salient features and also records authors field observations. As this book is intended exclusively for disease diagnosis, it should be read alongside authors another book - Poultry diseases -A guide for farmers & poultry professionals (2004) by J. L Vegad"- to obtain information on other aspects of poultry diseases, namely, cause, transmission, symptoms, diagnosis, treatment, and control. Although the book is written to meet requirements of poultry farmers, it will be equally useful to poultry consultants, diagnostic laboratories, and will acquaint the veterinary students with poultry diseases under field conditions.