Objective: The study aims to review the legal and regulatory status of complementary and alternative medicine (CAM) in the 27 European Union (EU) member states and 12 associated states, and at the EU/European Economic Association (EEA) level. Methods: Contact was established with national Ministries of Health, Law or Education, members of national and European CAM associations, and CAMbrella partners. A literature search was performed in governmental and scientific/non-scientific websites as well as the EUROPA and EUR-lex websites/ databases to identify documents describing national CAM regulation and official EU law documents. Results: The 39 nations have all structured legislation and regulation differently: 17 have a general CAM legislation, 11 of these have a specific CAM law, and 6 have sections on CAM included in their general healthcare laws. Some countries only regulate specific CAM treatments. CAM medicinal products are subject to the same market authorization procedures as other medicinal products with the possible exception of documentation of efficacy. The directives, regulations and resolutions in the EU that may influence the professional practice of CAM will also affect the conditions under which patients are receiving CAM treatment(s) in Europe. Conclusion: There is an extraordinary diversity with regard to the regulation of CAM practice, but not CAM medicinal products. This will influence patients, practitioners and researchers when crossing European borders. Voluntary harmonization is possible within current legislation. Individual states within culturally similar regions should harmonize their CAM legislation and regulation. This can probably safeguard against inadequately justified over- or underregulation at the national level.