This is the fifth edition of a textbook in spectroscopy intended for students of organic chem- istry. Our textbook can serve as a supplement for the typical organic chemistry lecture text- course in spectroscopic methods. This book is also a useful tool for students engaged in research. Our aim is not only to teach students to interpret spectra, but also to present basic theoretical concepts. As with the previous editions, we have tried to focus on the important aspects of each spectroscopic technique without dwelling excessively on theory or complex mathematical analyses. This book is a continuing evolution of materials that we use in our own courses, both as a supple- ment to our organic chemistry lecture course series and also as the principal textbook in our upper divi- sion and graduate courses in spectroscopic methods and advanced NMR techniques. Explanations and examples that we have found to be effective in our courses have been incorporated into this edition.