One of the most important developments of the twentieth century has been the movement of humanity into space with machines and people. The underpinnings of that movement- why it took the shape it did; which individuals and organizations were involved; what factors drove a particular choice of scientific objectives and technologies to be used; and the political, economic, managerial, and international contexts in which the events of the space age unfolded-are all important ingredients of this epoch transition from an Earthbound to a spacefaring people. This desire to understand the development of spaceflight in the U.S. sparked this documentary history. The extension of human activity into outer space has been accompanied by a high degree of self-awareness of its historical significance. Few large-scale activities have been as extensively chronicled so closely to the time they actually occurred. Many of those who were directly involved were quite conscious that they were making history, and they kept full records of their activities. Because most of the activity in outer space was carried out under government sponsorship, it was accompanied by the documentary record required of public institutions, and there has been a spate of official and privately written histories of most major aspects of space achievement to date. When top leaders considered what course of action to pursue in space, their deliberations and decisions often were carefully put on the record. There is no lack of material for those who aspire to understand the origins and early evolution of U.S. space policies and programs. This reality forms the rationale for this compilation. Precisely because there is so much historical material available on space matters, the National Aeronautics and Space Administration decided in 1988 that it would be extremely useful to have easily available to scholars and the interested public a selective collection of many of the seminal documents related to the evolution of the U.S. civilian space program up to that time. While recognizing that much space activity has taken place under the sponsorship of the Department of Defense and other national security organizations, the U.S. private sector, and in other countries around the world, NASA felt that there would be lasting value in a collection of documentary material primarily focused on the evolution of the U.S. government's civilian space program, most of which has been carried out since 1958 under the agency's auspices. As a result, the NASA History Office contracted with the Space Policy Institute of George Washington University's Elliott School of International Affairs to prepare such a collection. This volume and two additional ones detailing programmatic developments and relations with other organizations that will follow are the result. Copies of more than 2,000 documents in their original form collected during this project, as well as a data base that provides a guide to their contents, have been deposited in the NASA Historical Reference Collection. Another complete set of project materials is located at the Space Policy Institute at George Washington University. The documents selected for this volume are presented in four major sections, each covering a particular aspect of the evolution of U.S. space policies and programs. Those sections address: the antecedents to the U.S. space program; the origins of U.S. space policy in the Eisenhower era; the evolution of U.S. space policies and plans; and the organization of the civilian space effort. A second volume contains documents arranged in four sections addressing specific relations with other organizations: the NASA/industry/university nexus; civil-military space cooperation; international space cooperation; and NASA, commercialization in space, and communications satellites. A third volume describes programmatic developments: human spaceflight; space science; Earth observation programs; and space transportation.