INTRODUCTION: Clinical guidelines are advocated to improve the quality of care, especially for chronic diseases. However, the regulatory basis of clinical guidelines, their development, quality control, implementation and use as well as evaluation within countries across the European Union is not systematically known. METHODS: Using information collected from key informants in each country by means of a structured questionnaire, this mapping exercise illustrates the varied status of guideline production in European Union countries. RESULTS: Most European Union countries have an established national, regional or local clinical guideline programme, and a substantial proportion have developed guidelines on the prevention and management of chronic diseases. Several countries have mechanisms in place to ensure the quality of scientific evidence used for the development of guidelines is high and that the process is consistent and transparent. Others are only now taking an interest in guideline development and are taking the first steps towards establishing ways of implementing them. The majority of countries have no legal basis for the development of guidelines and those that have well established systems mostly implement them on a voluntary basis. The process of guideline development varies in its degrees of decentralisation across countries with many different types of organisations taking on this responsibility. There is general acceptance of the value of the instrument developed by the AGREE collaboration for evaluating the methodological robustness of guidelines. However, the extent to which guidelines are implemented in Europe is unknown, as there is no systematic data collection and, in most countries, no structure to enable it. There are few examples of formal evaluations of the development, quality, implementation and use of guidelines. CONCLUSIONS: Our findings call for renewed efforts to respond to the severe lack of standardized guideline terminology and accessibility as well as rigorous studies to evaluate the relationship between different ways to develop guidelines and their methodological quality, between their quality and the actual implementation and usage, and finally between implementation and health outcomes.