Analytical ultracentrifugation (AUC) is a powerful method for the characterization of polymers, biopolymers, polyelectrolytes, nanoparticles, dispersions, and other colloidal systems. The method is able to determine the molar mass, the particle size, the particle density and interaction parameters like virial coefficients and association constants. Because AUC is also a fractionation method, the determination of the molar mass distribution, the particle size distribution, and the particle density distribution is possible. A special technique, the density gradient method, allows fractionating heterogeneous samples according to their chemical nature that means being able to detect chemical heterogeneity. The book is divided into chapters concerning instrumentation, sedimentation velocity runs, density gradient runs, application examples and future developments. In particular, the detailed application chapter demonstrates the versatility and power of AUC by means of many interesting and important industrial examples. Thus the book concentrates on practical aspects rather than details of centrifugation theory. Both authors have many years of experience in an industrial AUC research laboratory of a world leading chemical company.