The book contains extensive clinical and basic experimental research findings about new therapeutic targets in the form of substance P and its antagonists. Substance P has been reported to be involved in the patho-physiology of various diseases such as pain, inflammation, depression, GIT, HIV, asthma etc. Focusing this relatively new but therapeutically potential area of research, could lead to the discovery of some outstanding molecules of clinical utility in their respective classes. Though lot of research work has been done, much more is required to authenticated their clinical.