Ayurveda, the Indian system of medicine is an ancient science of diagnosis and treatment. It has developed its own ways to inspect, interpret and diagnose the diseases of a patient to prescribe suitable treatment. However, there are basic principles to understand them in the limited explanation. In order to diagnose the disease on the basis of Ayurvedic principles, the physician should know the subtle changes occurring inside the body due to the imbalance of Dosha (Three body humors). Specific investigation methods explained in Ayurveda for various Srotas (systems) and diseases related to it should also be studied thoroughly. A systematic application of these diagnostic techniques assists in determining the right treatment to permanently cure the disease. This book contemplates the concepts of various principles of diagnostic methods in Ayurveda and its interpretation with modern parlance.