The article focuses on the compatibility of criminal law anti-terrorism legislation in Danish law with basic principles regarding the rule of law and due process. The so-called anti-terror-packages of 2002 and 2006 involve a set of rather uncertain and wide-reaching provisions fundamentally challenging the principle of legality and substantially widening of the scope of criminal law. These provisions criminalize various activities more or less remote from actual or attempted terrorist acts and participation in such activities, too. The legislature has even over-implemented vari-ous legal instruments binding on Denmark by virtue of EU law or international obligations. And the statutes have been drafted in a somewhat loose manner without sufficiently thorough legislative preparations. The provisions in the Penal Code constitute an anchorage point for all other anti-terrorism legislation. Thus, the challenges regarding rule of law and due process also relate to secondary legislation in fields like law enforcement, criminal procedure, intelligence, public law, treatment of foreigners, etc.