Large-scale research infrastructures (RI) are increasingly needed by science, technology and education. The biggest and most powerful ones of such RIs in physical and engineering sciences are, as a rule beyond the needs and financial possibilities of one nation and are, therefore, built and operated in frames of an international collaboration. Besides the most powerful accelerators in high-energy and nuclear physics, giant lasers, major neutron sources, synchrotrons, free-electron lasers, special telescopes, and some others belong to this class of RIs. Examples are ESRF, ILL, European XFEL, FAIR, etc.

Although most international RIs are of open-access character and individual proposals for using those facilities are, in principle, refereed exclusively on the basis of scientific excellence, a long-term access is, understandably, made only possible for scientists of full or associate members of the international RI. The condition of membership is a minimum contribution of 1–4 % of the budget of the RI. Unfortunately, small and medium-size countries cannot afford paying the high membership fee and, therefore, their scientists are handicapped in using the best European RIs.

An obvious and well-known solution of this problem is forming consortia of shareholders from small and medium-size countries that may be able to meet the condition of the minimum membership fee. Indeed, such consortia have already been formed and successfully operated. Examples are Centralsync, a consortium of the Czech Republic, Hungary and Slovakia to ESRF and CENI, a consortium of Austria, the Czech Republic, Hungary and Slovakia to ILL.

So far consortia have been always formed in a troublesome bottom-up process. In 2014, the European Physical Society (EPS) launched a project to foster the formation of consortia of governmental shareholders from small and medium-size countries to the best European RIs in physical and engineering sciences.

The workshop is an important milestone of this project. It aims to bring together RI policy-makers of the European Commission and of European governments, the managements of major light sources and similar RIs with representatives of interest groups of scientists from Central and Eastern Europe as well as other parts of the continent. The main objective of the workshop will be to discuss the possibilities of organising consortia to major Pan-European RIs and networks of existing RIs of the region. General discussion will take place in a round-table discussion the outcome of which will be summarised during the closing session.