Cluster Ion-Solid Interactions: Theory, Simulation, and Experiment provides an overview of various concepts in cluster physics and related topics in physics, including the fundamentals and tools underlying novel cluster ion beam technology. The material is based on the author's highly regarded courses at Kyoto University, Purdue University, the Moscow Institute of Physics and Technology, and the Moscow Engineering Physics Institute as well as his research results on cluster ion beam applications at Kyoto University. The author introduces the basic principles of statistical physics and thermodynamics before covering applications, experimental justifications, and practical implementations. He describes classical nucleation theory and explains the drawbacks of this theory, showing how accurate modeling and simulations are necessary to justify theoretical approaches and simplifications.