Political parties in the Netherlands have been calling for a ban on Hizb ut-Tahrir for years. But what do we actually know about this movement, its supporters and how they relate to Dutch society? This article is one of the first attempts to paint a more complete picture. It shows that the movement and its supporters adhere strictly to the course of the (re) establishment of the caliphate that was mapped out by founder Taqiuddin al-Nabhani in the 1950s. However, the assumption that the movement would advocate or encourage the use of violence requires nuance. These insights are not ‘static’ or ‘comprehensive’ and should be seen as a contribution to the discussion of the nature of the movement. The question of how the course – ideas and activities – of Hizb ut-Tahrir relates to democratic society will be addressed in a subsequent article.