Undesirable migrants can include asylum-seekers believed to have committed crimes before arriving in the host State, immigrants who had their status revoked for having committed crimes in the host country, or immigrants who were not granted a status, or had their status revoked because they are considered to pose a current or future security concern. These undesirable migrants can be unreturnable because of different legal and practical reasons. This article describes the size and characteristics of this group and discusses which policy measures the Dutch Government takes to deal with this group, in particular in relation to access to permits, return, relocation, and prosecution. It concludes that the Dutch approach to bar Article 1F-excluded persons under the Geneva Convention and Protocol Relating to the Status of Refugees from all residence permits is in certain circumstances at odds with European Union law.