Summery: What is the relationship between religious orthodoxy and psychological, social and political integration of Turkish Dutch Muslims? Orthodox interpretations emphasize that a ‘pure’ Islam is about essential and inerrant truths that provide strict guidelines for everyday life. In the present sample, half of respondents reported (very) strong orthodox beliefs. Orthodoxy was higher among younger compared to older respondents and among those who perceived relatively high levels of rejection of Muslims in the Netherlands. Orthodoxy was negatively associated with national identification but not with national disidentification or with social integration. Orthodoxy was strongly and positively associated with the endorsement of Muslim rights and the attitude towards democratic political organization of Muslims in the Netherlands. Orthodoxy was not related to political (in)tolerance. Together, the results indicate that orthodox beliefs do not necessarily hamper the integration of Turkish Dutch Muslims.