Products arising from modern biotechnology provide new opportunities to achieve sustainable productivity gains in agriculture. Concerns over their possible environmental  and health implications stimulated regulatory mechanisms for food safety and environmental risk assessment. Over the past two decades, national biosafety frameworks, guidelines, and regulatory systems have often been implemented on a 'piece-by-piece' basis in response to the demands or urgent needs of the moment. Ideally, a biosafety system would be developed from a comprehensive plan. However, building such a system and making it operational is complicated by the fact that there is no single best approach nor standard that reflects national environmental, cultural, political, financial, and scientific heterogeneity. Given these challenges and difficulties inherent in building regulatory systems and needed capacity, the International Service for National Agricultural Research (ISNAR) convened an expert consultation in July 2001. The purpose of this meeting was to develop a conceptual framework to address regulatory implementation and capacity-building needs of developing countries and Parties to the Protocol. The conceptual framework clarifies critical decision points in the development of a national biosafety system, systematically examines choices among policy options, and delineates some of the scientific and social dimensions of these options. It complements ongoing regional and global projects that facilitate the development of national biosafety guidelines and frameworks.