Fluid mechanics, solid-state diffusion and heat conduction are deeply interconnected through the mathematics and physical principles that define them. This concise and authoritative book reveals these connections, providing a detailed picture of their important applications in astrophysics, plasmas, energy systems, aeronautics, chemical engineering and materials science. This sophisticated and focused text offers an alternative to more expansive volumes on heat, mass and momentum transfer and is ideal for students and researchers working on fluid dynamics, mass transfer or phase transformations and industrial scientists seeking a rigourous understanding of chemical or materials processes. Accessible yet in-depth, this modern treatment distils the essential theory and application of these closely related topics, includes numerous real-world applications and can be used for teaching a range of related courses in physics, engineering and materials science departments.