This book is about instruments and their use on airborne and spaceborne platforms. It is divided into three major sections covering more than 150 spaceborne mssions and sensors, over 300 airborne sensors as well as reference data and definitions. Four extensive appendices provide a comprehensive survey of campaigns, glossary, acronyms and abbreviations and an index of sensors. An effort has been made to present the information in context, to point out relationships and interconnections for a better understanding of the subject. The book may serve as a reference and guide to all involved in the various national and international space programs: researchers and managers, service providers and data users, teachers and students.