Industrial accidents that affect international water bodies can put the water supplies and ecosystems of many countries at risk. Hence, joint, cross-border contingency planning is essential. These checklists offer a systematic and harmonised approach to identifying and assessing the risk of transboundary water pollution. They are based on the main principles of the UNECE conventions on industrial accidents and water body protection. They provide examples of how pollution can be controlled as well as recommendations for efficient cross-border cooperation.