The chemicals industry - including industrial chemicals, pharmaceuticals, pesticides, food and feed additives and cosmetics - is one of the world's largest industrial sectors. Many chemical products are traded internationally. Varying national requirements can mean duplication of efforts and significant costs for the chemicals industry, as well as posing barriers to trade. By agreeing on test methods and data quality and sharing the workload of chemical safety testing and assessments, countries together achieve environmentally sustainable and cost-effective results. For non-clinical health and safety testing, for example, the results of such studies carried out on a chemical product in one OECD country must be accepted by the others as long as it was carried out in accordance with the OECD Test Guidelines and Principles of Good Laboratory Practice. This saves the chemicals industry the expense of duplicative testing for products that are marketed in more than one country. This report analyses the rigorous and comprehensive system for assessing and managing chemicals that helps governments and industry save about EUR 150 million each year, through "work sharing" facilitated by the OECD.