The astrophysical process of accretion onto compact central objects is ubiquitous across the universe. The study of white dwarf stars has greatly expanded in recent years, and this book presents, from first principles, the physics of the accretion process onto white dwarfs. Among the resulting phenomena are isolated white dwarfs accreting interstellar gas and dust as they orbit the galactic center, white dwarfs accreting from the debris disks of tidally disrupted asteroids, comets and exoplanets in other exoplanetary systems, white dwarfs accreting from red giant winds in symbiotic variable stars, white dwarfs accreting from Roche lobe-detached main sequence stars, white dwarfs accreting in cataclysmic variables, helium accreting white dwarfs in the ultra-compact AM CVn binaries, accreting white dwarf explosions in classical novae and Type Ia supernovae, the cosmologically critical white dwarf supernovae that led to the discovery of the accelerating expansion of the universe and the existence of dark energy. This book is intended for advanced undergraduates, graduate students, astrophysicists who specialize in white dwarf studies as well as non-specialist scientists. Key Features: Describes the accretion process onto white dwarf stars across a broad range of astrophysical settings Provides an up-to-date reference for both students and researchers in astrophysics in a rapidly evolving field Includes the basic physics of non-accreting white dwarfs and the physical processes that occur Author is a well-known expert on white dwarf stars Contains helpful appendices tabulating the fundamental parameters of accreting white dwarfs