This book is a modern presentation of multiphase flow, from basic principles to state-of-the-art research. It explains dispersed fluid dynamics for bubbles, drops, or solid particles, incorporating detailed theory, experiments, simulations, and models while considering applications and recent cutting-edge advances. The book demonstrates the importance of multiphase flow in engineering and natural systems, considering particle size distributions, shapes, and trajectories as well as deformation of fluid particles and multiphase flow numerical methods. The scope of the book also includes coupling physics between particles and turbulence through dispersion and modulation, and specific phenomena such as gravitational settling and collisions for solid particles, drops, and bubbles. The eight course-based chapters feature over 100 homework problems, including theory-based and engineering application questions. The final three reference-based chapters provide a wide variety of particle point-force theories and models. The comprehensive coverage will give the reader a solid grounding for multiphase flow research and design, applicable to current and future engineering. This is an ideal resource for graduate students, researchers, and professionals.