Chemicals in food can pose a risk to human health. The Codex Alimentarius Commission (CAC) provides a global framework for the risk management of these chemicals, from setting maximum residue limits for veterinary drugs and pesticide residues in food to maximum levels (MLs) for contaminants in foods. Codex standards are based on science provided by independent scientific bodies from FAO and WHO. This chapter outlines the work of Codex on food chemical risk management with a focus on contaminants in food. It discusses how its standards relate to food trade and WTO agreements, the legal basis of its standards, its working procedures and the scientific basis for standards, considerations other than science and future challenges.