This is a 1989 internal NASA report prepared for NASA Administrator Truly by a team led by Johnson Space Center Director Aaron Cohen. It was commissioned by Admiral Truly after the Presidents July 20, 1989 speech, and its purpose is to provide a database for the Space Council to refer to as it considers strategic planning issues. The report will be used as an input and one data source for Council consideration of approaches to program, schedule and technology, international cooperation and management. The Space Council will examine the reference cases described in the report and also intends to examine a range of robust technical alternatives and approaches to mission planning. The report does not contain any specific recommendations. The report does not contain any estimates of total mission cost. The report does provide information regarding the potential benefits of the human exploration initiative, international participation considerations, and potential management system enhancements.