Within the European Union, directorates-general are departments of the European Union government with specific zones of responsibility, the equivalent of ministries at a national level. Most are headed by a European Commissioner, responsible for the general direction of the directorate-general, and a Director-General, responsible for the management of day-to-day affairs The European Patent Office (part of the European Patent Organisation, separate from the EU) also has Directorates-General, which are administrative groupings of departments.