The inclusion-moderation thesis hinges on the idea that competitive electoral processes tame radical ideas thereby leading to the transformation of extremist parties into more moderate ones. The theory offers a causal process: as parties are included in their electoral systems, the competitive processes and negotiations move them from the tail end of their ideological spectrums to positions that are more acceptable to broader constituencies. While the theory offers an affirmative view of the incorporation of all parties to electoral competition, it poses many questions ranging from whether such transformations are inevitable or strategic to if and how inclusion leads to the capture of the entire political system by radical ideas. A review of the existing research shows that it pays more attention to parties' overall policy commitments and privileges the position of party leadership. Focusing on the overall impact of moderation much research disregards the impact of internal party dynamics, emphasizes the utility of centralization of power or hierarchical structures and their tendency to promote moderation. One of the paradoxical findings of such studies is the assumption that moderation does not require democracy yet still promotes democratic results. More important, the theory makes several assumptions about inclusion without carefully identifying how democratic the electoral context is, the ways in which voters stand in their respective political spectrums or how they reward and punish parties that subscribe to extremist or moderate positions. The evidence suggests that inclusion-moderation cannot be reduced to a mechanical process; the ideologies of extreme parties, the overall context of competition and electorates’ decision making processes need to be taken into account to understand if and how electoral inclusion can alter parties’ commitments and policies. Inclusion may lead not only to procedural adjustments, while keeping extremist ideologies in tact but also to ideational transformation that makes extremist parties more prone to recognize and negotiate with other groups. When the context is not democratic moderation might mean domestication of parties with what may appear to be “extremist” or “radical” in context thereby thwarting the overall democratization of the system. Some analyses also show exclusion may lead to the moderation of extremist parties. Given the contradictory evidence, the insights of the inclusion moderation model cannot serve as a one-size-fits all model but help to understand how the inclusion process works by presenting an ideal type for both party and electoral behavior while both conformity and divergence from the model offer important insight to democratic processes and democratization.