Ungerer, Jameson Lee. (2012) Assessing the Progress of the Democratic Peace Research Program. International Studies Review, doi: 10.1111/j.1468‐2486.2012.01103.x This article analyzes the evolution of the democratic peace, beginning from the initial observation of a lack of wars and rarity of conflicts between democratic regimes to a number of competing and/or compatible explanations over the causality of the observed peace. A Lakatosian methodology is applied as a foundation for assessing the progress of the research program, according to the four traditionally recognized concepts: a hard core; a positive heuristic; a negative heuristic; and the auxiliary hypotheses. Theories are distinguished based on their theoretical and empirical progressiveness, as well as progressive intra‐program problem‐shifts. Explanations over the active causal process have often been seen as competitors, yet a Lakatosian framework enables seemingly inconsistent hypotheses to be grafted onto an existing research program, which can be determined to be progressive if they provide increased explanatory power and novel predictions that receive empirical corroboration. By these criteria, the research on capitalist development and the ongoing democratic peace research are not incompatible, provided that further additions to the research program ascertain the progressive criteria. Furthermore, by highlighting the areas that can best explain and predict the democratic peace phenomenon, the Lakatosian analysis offers insights for future progression in the field, as well as the areas upon which research should be focused.