This book presents the fundamentals of low gravity fluid dynamics and heat transfer. It investigates fluid behavior in low gravity environments such as those found in earth orbiting and space vehicles. The two major fluid phenomena affected by gravity (buoyancy and surface tension) are treated thoroughly from both the theoretical and applications points of view, and limitations of fluid and thermal responses to gravitational fields in space-based settings are clearly delineated. Summaries of all data available from low gravity flight and terrestrial experiments performed to date are also presented.