The best part in treating the disease is the prompt diagnosis and appropriate treatment. Endo- perio lesion is one such common dental lesion that involves interdisciplinary approach in treating and following up the condition. This textbook extensively discusses various etiologic factors, contributing factors, classification, signs, symptoms, various diagnostic aids, sequelae, prognosis, treatment plan of endo-perio lesion. This text book also discussed about the controversy involved in this condition.