It seems likely that no project of this magnitude is undertaken in the absence of several motivations. This book is no exception. There are, from our perspective, at least two rational reasons for conducting this cataloging and organizational effort. The first of these is the obvious fact that a very large number of macrocyclic polyethers have now been prepared and nowhere is there a comprehensive listing of them. A number of excellent reviews have been published dealing with one or more aspects of macrocycle chemistry, but we felt a great need for a single source listing known compounds. We have, the- fore, attempted to provide such a listing to assist ourselves in keeping track as well as, we hope, helping others in this field. We also felt that there was a need for a survey of methods which have been utilized in the syntheses of these cation binders so that the novice could establish some starting point. Wherever possible, we have also attempted to point to the motivations which enΒ gendered the various syntheses. The somewhat irrational reason which propelled us into this endeavor was the quesΒ tioning of Charlie Morgan who often asked if one or another obscure compound had been synthesized. As often as not, we were uncertain arid now at least have a reference which, if not absolutely complete, will at least save face.