This book presents detailed studies of flows in elastic liquids - from theory, through experiment, to applications. Falling into the category of elastic liquids in particular, are the melts and concentrated solutions of such flexible-chain polymers as polyethylene, polyisobutylene and polypropylene, all of which are widely used in polymer processing. The reading material is presented with an emphasis on practical applications. Experimental methods, experimental device schemes, principal rheological effects and dependencies are considered, as are the constitutive equations consistent with thermodynamics which are able to describe experimental data, and the methods of evaluation of rheological parameters within these equations. Numerous comparisons are made between predictions and experimental data that demonstrate which properties of the constitutive equations are particularly related to one or another effect. Applications of results to industrial problems are also discussed. This book should be of interest to those working in research and development in the field of polymer processing, as well as in the food and oil industries. It is aimed at polymer rheologists, gels and food scientists; senior undergraduates, graduates and researchers working in the fields of polymer and food processing as well as the oil industry.