This book introduces the nature, causes and impact of plant diseases. It briefly describes the history of plant pathology as a scientific discipline and introduces the disease cycle as the key tool for understanding disease development and devising appropriate management strategies.It addresses the mechanisms of pathogenicity and immunity. It explores the biology of the interactions between plants and plant pathogens from the cellular level to the population level, with the chapter addressing epidemiology. The book then concerns the approaches we can take to alleviate the effects of plant pathogens.Print edition not for sale in India.