Crime prevention standards in housing have for a long time been limited to target hardening, and in that respect European Norms were developed as guidelines for 'burglar resistant' doors, windows and shutters (EN1630). Recent developments include a set of supplementary crime prevention standards in the building sector, which are not limited to technical products but focus on the layout and management of urban environments and their impact on public safety. This article focuses on the problem of systematic Europe-wide implementation of crime prevention standards in urban planning. The attempt to implement common guidelines for design-led crime prevention through the development of a European Norm has failed. In this article the author will first introduce the system of standardization and then examine the particular European Standard for Crime Prevention by Urban Planning and Building Design (CEN/TR14383). Instead of a harmonious application of that standard in Europe, a variety of policies have been negotiated, including national standardization, consulting schemes and liaison systems based on rewards. Moreover the standard has been re-interpreted in some jurisdictions as 'gender mainstreaming', and it has been adopted by police to organize national training for local governments. The author will present and compare examples from Denmark, the UK, the Netherlands, Austria and Poland to show the divergent ways of interpretation and practical implementation of guidelines in design-led crime prevention. Abstract published by arrangement with Sage Journals.