The child labor evidence review examines the existing causal evidence on child labor and child work targeted for elimination. Child labor refers to the engagement of children in prohibited work. While the definition of child labor is guided by International Labour Organization (ILO) conventions and resolutions, there is no single definition across nations. Moreover, definitions may change over time, and the terminology and concepts used to categorize child labor (and to distinguish from working children) may be inconsistent in published studies and research reports. CLEAR acknowledges differing definitions of child labor by country but does not validate the definition of child labor or assess the validity of authors’ constructs within individual studies for the country in which the program or intervention being examined occurs. For each study in the review, CLEAR assesses the quality of the causal evidence and summarizes its approach, findings, and the intervention examined.