This is an interdisciplinary reference providing a complete breakdown of the theories, techniques and applications of turbulent drag reduction by surfactant additives, from leading researchers in the field. Covering the latest developments in the field of drag reduction (DR) by surfactant additives, this book explains the types of additives used, the mechanisms by which DR is achieved and the experimental and numerical techniques needed to understand the topic. It covers turbulent drag reduction, heat transfer reduction, complex rheology and the real-world applications of drag reduction. It introduces advanced testing techniques, such as PIV, LDA, and their applications in current experiments, illustrated with multiple illustrations and equations. Real-world examples of the topic’s increasingly important industrial applications enable readers to implement cost- and energy-saving measures. It explains the tools before presenting the research results, to give readers coverage of the subject from both theoretical and experimental viewpoints. It consolidates interdisciplinary information on turbulent drag reduction by additives, and is helpful for researchers, students and engineers as a reference.