The search for bioactive compounds has been rewarded by plants, as they are the richest source of these secondary metabolites. The leads provided by them are often instrumental in the development of safer and more potent formulations. Consequently, Phytochemical research has lately undergone explosive growth and forms the cornerstone of modern bio-organic chemistry. This boost is an outcome of better isolation/ purification methods and advancement in sophisticated analytical techniques. Of late, natural product chemists have also started exploring the same family but different species in this pursuit. This has yielded plethora of novel compounds, with interestingly increased in biological activities. This Book deals with various aspects of Natural Product Chemistry such as isolation, of alkaloids, xanthones and iridoid glycosides, sterols etc and their characterization by use of spectroscopy techniques such as UV, IR. 1HNMR, 13C NMR, DEPT experiments and Mass spectroscopy. This can be very useful for research students undertaking Master’s and Ph. D. courses. The original spectra at the end of the Book will help the students in interpretation of spectra of their compounds.