The profession of laboratory medicine differs between countries within the European Union (EU) in many respects. The objective of professional organizations of the promotion of mutual recognition of specialists within the EU is closely related to the free movement of people. This policy translates to equivalence of standards and harmonization of the training curriculum. The aim of the present study is the description of the organization and practice of laboratory medicine within the countries that constitute the EU. A questionnaire covering many aspects of the profession was sent to delegates of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) and Union Européenne de Médecins Spécialistes (UEMS) of the 28 EU countries. Results were sent to the delegates for confirmation. Many differences between countries were identified: predominantly medical or scientific professionals; a broad or limited professional field of interest; inclusion of patient treatment; formal or absent recognition; a regulated or absent formal training program; general or minor application of a quality system based on ISO Norms. The harmonization of the postgraduate training of both clinical chemists and of laboratory physicians has been a goal for many years. Differences in the organization of the laboratory professions still exist in the respective countries which all have a long historical development with their own rationality. It is an important challenge to harmonize our profession, and difficult choices will need to be made. Recent developments with respect to the directive on Recognition of Professional Qualifications call for new initiatives to harmonize laboratory medicine both across national borders, and across the borders of scientific and medical professions.