The process of assessing the risks to health from exposure to hazardous substances is a key step in ensuring that work is safe. It requires systematic collection of information about the work activities, the substances used or produced during the work, and the steps that have been taken to protect the worker. Skin exposure is a major route of exposure for substances into the body, which, depending on the substance, may cause acute systemic effects such as cardiovascular, lung, and/or neurological toxicity or chronic effects such as kidney disease or cancer. Skin exposure may also cause local effects such as contact dermatitis (irritant or allergic) or skin cancer. This chapter sets out the general approach that should be taken in assessing risks from skin exposure and the approaches that can be taken to help improve the reliability of exposure assessments, including the use of measurements or modelling of skin exposure. It also outlines key steps in the control of skin exposure.