We are again proud to present an excellent volume of contemporary topics in NMR and EPR to the biological community. The philosophy behind the volume and the presentation of each chapter remains at the high level reflected in our earlier volumes: to be current, pedagogical, and critical. The first chapters, as always, address a subject related to in-vivo biology. Gabby Elgavish addresses NMR spectroscopy of the intact heart. lain Campbell and colleagues present a state-of-the-art description of NMR methods for probing enzyme kinetics in intact cells and tissues. Klaus Mobius and Wolfgang Lubitz have produced a thorough review of the principles and applications of ENDOR spectroscopy in photobiology and biochemistry including discussions of liquid and solid state ENDOR as well as CIDEP-enhanced ENDOR. The final chapter by Hans Vogel and Sture Forsen addresses a contemporary problem in inorganic biochemistry, namely cation binding to calcium binding proteins. We are pleased to announce that a special forthcoming volume will be devoted entirely to the subject of "Spin Labeling: Theory and Applications (3rd compendium)." A substantial degree of progress has occurred in this important area of ESR in biology since the last treatise on the subject in 1979. Lastly, we acknowledge our colleagues in the field who continue to support this excellent series both as subscribers and contributors. We pledge to continue servicing the community as long as the need exists.
