The history of man might be considered as an ever increasing quantity and quality of measurements. Measurements related to space have been made by early astronomers, modern astronomers, and now by aerospace technologists. The manned lunar landing, a major national goal, has given us the means to measure in space. The space vehicle development itself has made heavy demands on instrumentation; this is discussed in some detail in this paper. The advantages of the International System of Units are mentioned. Some examples are used to illustrate the future of space measurement.