Observable implications ofthree existing theories of the Islamic advantage -- grievances, faith, information -- are tested using a variety of data sources. Contrary to the expectations of grievance theory, individuals in the Muslim world appear to be more dissatisfied and less apathetic. Moreover, participation rates are lowest among the most aggrieved, much as they are elsewhere in the world. In contrast to what the faith-based theory expects, participation rates are significantly lower among individuals with the strongest religious beliefs. Further, the popularity of Islamic-based political and economic movements does not appear to follow trends in religiosity in the aggregate, neither across space nor across time. Instead, support for these movements appears to come from both the religious and the secular, in Turkey and across the Muslim world. Finally, there is little evidence that voters in Muslim countries are uninformed, generally, or better informed about Islamic-based parties, in particular. The lack of support for the all three existing theories reopens the puzzle of Islamic-based movements yet again.