Complex fluids are substances that are neither really liquid nor really solid in the classical sense. They include polymers, colloids, emulsions, forms, gels, liquid crystals, surfacants, and other materials that form flowable microstructures. These substances are important in industries producing polymers, such as plastic packaging, colloids, such as paint, foods, such as ketchup, and consumer products, such as toothpaste or shampoo, as well as countless other products in the petroleum, microelectronics, pharmaceutical, and other industries. This textbook provide both an introduction to these fascinating and important substances and an up-to-date synopsis of the latest advances in understanding the relationship between their structure and flow properties. Similarities and differences among the various types of complex fluids are emphasized. The book is easy to read, lavishly illustrated, and filled with interesting problems, worked examples. and practical applications. With its "trunk and branch" organization of chapters, it is intended to be used as a textbook for a one or two semester graduate-level course in engineering, materials science, or physics, as a monography for academic and industrial researchers, or as a reference book for researchers and educators.