Radial Basis Functions (RBFs) are a powerful numerical methodology for solving PDEs to high accuracy in any number of dimensions. The ability to apply RBFs to a wide range of problems, including fluid mechanics, wave motions and geosciences, makes them a vital tool for graduates and researchers specialising in many application areas, ranging from numerical analysis to geoscience. Using examples and heuristic explanations to generate a practical and intuitive perspective, this book addresses how, when, and why RBF-based methods work. The logical progression of the book, beginning with an introduction to finite difference (FD), ensures a comprehensive study of RBF-RD methods which are fast becoming a dominant methodology for numerical simulations in a wide range of applications. As the first book to survey RBF-FD methodology, the value this text brings to graduates and researchers is unparalleled.