Establishment of such a system faces difficulties due to variations in the information available, technical problems, language barriers, and the influence of cultural, social, economic and legal factors on crime and the criminal justice system. In designing such a system, consideration must be given to information needed for policy planning and decisionmaking in individual cases. Information content and date validity and reliability issues will have to be addressed. The resources and information needs of system data suppliers and users also must be determined. Suppliers and users generally will be the same and will include national ministeries of justice, national and local criminal justice agencies, international and regional intergovernmental and nongovernmental organizations, and researchers and scholars. Questions regarding access to the system also will require answers. Based on past experience, the emphasis of information content of the system should be on national laws and practice; statistical data; and information on research, policies, and programs. Development of such a system will require careful planning and knowledgeable people who know what data are needed, in what form they are needed, and how to get them to those who need them.