This book explains the foundations of pulse EPR, a field of spectroscopy which has now come of age and has found widespread application in investigations of structure, dynamics, and function of biological systems and synthetic materials. For the first time a systematic overview of the whole field is given, including coverage of Fourier-transform EPR, relaxation measurements, electron spin echo envelope modulation (ESEEM), pulse electron- nuclear double resonance (ENDOR), pulse electron-electron double resonance (ELDOR), transient nutation, and a number of advanced techniques. Researchers approaching the field will find here the basic theory as well as a description and critical evaluation of the existing methods needed for selecting the proper experiment, conducting it, and analysing the results. The experienced researcher active in the field should find this book a useful reference and a guide to adapting EPR pulse sequences to new problems.