This practical handbook provides the reader with enough background and specific information to begin conducting thermal analysis and to participate in the thermal design of spacecraft systems. The book is a revised and updated edition of Satellite Thermal Control Handbook, published in 1994. The name change reflects the expanded scope of this work, which now includes thermal environments and design techniques for interplanetary spacecraft, in addition to the Earth-orbiting satellites that were the focus of the original handbook. The reader will find an updated characterization of the thermal environment in Earth orbit, new material documenting the environments of interplanetary missions, more detailed information about each of the thermal control hardware elements found in the first edition, and presentation of some newer technologies such as heat switches and precision temperature control techniques.