This project, to be conducted under the guidance of the US National Committee for the Committee on Data for Science and Technology (CODATA) of the International Council of Scientific Unions (ICSU), will consist of an interdisciplinary study of international access to scientific and technical (S&T) data. The primary focus of the study will be on d ata in electronic form, a topic of increasing complexity and importance in scientific research and international collaboration. It will begin by outlining the needs for data in the major research areas of current scientific interest in the astronomical, biological, geological and physical sciences. It will then characterize the legal, economic, policy, and technical factors and trends that have an influence on access to data by the scientific community. It will also identify and analyze the barriers to international access to S&T data. The study will recommend approaches that might help overcome barriers to access in the international context. NSF is sharing support for this project w ith several other Government agencies, including DoE, NASA, NIH, NIST and NOAA.