satellite technology and its Earth-oriented applications have evolved enormously since the early days of the space age. In the early 1960s, the potential of satellites to contribute to international communications and national and regional weather forecasting was quickly recognized, and the first experimental satellites were launched. The benefits of the early experiments were sufficiently convincing that operational communication and meteorological satellite systems were functioning by the mid-1960s. Remote sensing, which posed more difficult technological problems, began experimentally in the early 1970s and quickly became technologically operational, although there are still organizational questions concerning operational satellite remote sensing that need to be resolved. The papers in this volume describe work currently underway in the further development of satellite technology and Earth-oriented applications. They include developments in communications, meteorology, and remote sensing in a variety of developed and developing countries. The field of satellite technology and applications is so vast today that such a collection of papers cannot begin to cover the full range of activities, but can only offer some highlights of current work. Nonetheless, the collection as a whole does accurately reflect a number of aspects of the international structure of technological development.