This article studies a novel factor relevant for the moderation of an Islamist party: the degree of dependency on a social movement organization. This question is examined in a case study analysing the evolution of the relationship between the Moroccan Islamist party, Party of Justice and Development (PJD), and its founding social movement organization. Over time, the PJD has been gaining autonomy, becoming more moderate and simultaneously gaining strength. Contemporaneously, liberalization in Morocco has been partially reversed, partly as a result of the rising Islamist strength. These findings suggest that it is the strength of the Islamist opposition, rather than its ideological rigidity, that makes MENA rulers reluctant to liberalize. We study the implications of these findings for European Union policy towards Islamist parties in the MENA region.