While work is a fundamental human activity and work of some kind is central to the lives of very many children worldwide, inappropriate work can be harmful to them and hinder their development. This entry is primarily about such work that impinges on the well-being of children, and which is commonly categorized as child labor. After commenting on the term child labor, the entry presents criteria for assessing when and how work can be harmful to children. It goes on to consider why children undertake harmful work and points to a variety of strategies to protect children from harm in work. Finally, this entry examines debates surrounding current international policy on child labor and its definitions.