This article applies Diehl and Druckman’s evaluative framework to the case of the United Nations Transitional Authority in Cambodia (UNTAC, 1992-1993), finding it to be of high utility in analyzing the record of this operation. By directing the analyst to evaluate discreet objectives within three goal categories, Diehl and Druckman encourage the disaggregated evaluation that, I argue, holds most value for scholars and practitioners seeking to explain the outcomes of peace operations. In particular, this approach requires that the underlying purposes and normative agendas that always color evaluation be explicitly addressed. The article finds that UNTAC was a partial success and, more importantly, suggests a number of refinements to strengthen Diehl and Druckman’s framework. First, it recommends greater analysis of the relationship between a peace operation’s roles of action and reaction. Second, the case of UNTAC demonstrates the need for time-series evaluation to be based on sufficiently regular measurement if it is to capture very short-term patterns of conflict, such as wet- and dry-season violence cycles. Finally, the article questions the appropriateness of including ‘good relations with the local population’ as a dependent variable to be evaluated, recommending instead that such outcomes be considered by assessing the social costs of peace operations to host societies.