The challenges confronting food safety at an international level have increased dramatically over the last decade as the food supply has become more global. The potential hazards are varied and complex and encompass chemical, microbiological, and radiological threats. Chemical hazards include those that may occur naturally or are anthropogenic and are introduced into the food supply inadvertently or deliberately. Recent events like the melamine and analogues in pet food and infant formula and the tragic consequences of the Japanese earthquake and tsunami have highlighted the impact that these threats can have on an international level. In the past, these episodes have been usually confined to national boundaries and have tended to impact food safety on a country by country basis. With food now traveling great distances to new markets, the negative consequences have an impact around the world. The WHO is the sole international public health organization that can co-ordinate the appropriate public health response in dealing with these international food crises. Some of the issues that will be addressed and described will be the following: the integration and use of new science in the assessment of the hazards and risks of chemical threats, new approaches/methodologies to assess the safety/risk to the global food supply, and new technologies that are being brought to bear to facilitate the detection of chemically contaminated foods. The mechanisms and approaches that have been developed under the auspices of the WHO will be described and will include actual case monitoring strategies for proactively and retroactively detecting and responding to outbreaks of chemical food contamination.