This book elucidates the peculiar phenomenon of entropy/enthalpy compensation that takes place in high performance liquid chromatography (HPLC) of polymers. Numerous publications, including some books, are devoted to molecular characterization of synthetic polymers, materials presently produced in large and steadily growing quantities, applying methods of HPLC. A knowledge of the molecular characteristics of polymers is indispensable, not only for their proper applications but also for their recycling and remediation. Polymer scientists generally focus on synthesis and potential applications of polymers while not giving due attention to an important central link, their comprehensive characterization in context of development of structure-property correlations. To fill this gap is one of the aims of the present book. The process of entropy/enthalpy compensation plays a decisive role in the advanced method of polymer characterization such as liquid chromatography at critical conditions, eluent gradient interaction chromatography, and temperature gradient interaction chromatography. All chemists working on any aspect of polymer science will find this book a valuable resource for the development of structure-property correlations.