this article examines the recent debate on the position of syari'ah in indonesian constitutional amendments (1999–2002). the article operates at two levels: a historical review of the debate on islam and state in indonesia and a theoretical effort to situate the indonesian debate in the broader context of debates over islam and constitutions. it argues that the rejection of the proposed amendment to article 29, dealing with islam, has shown that indonesian islam follows the substantive approach of syari'ah, not the formal one.