The Eighteenth Cospar Meeting and Symposia were held from May 29 to June 7, 1975, in the Palace of Culture and Sports in Varna, Bulgaria, at the invitation of the Bulgarian Academy of Sciences. The meeting was under the patronage of Stanko Todorov, Chairman of the Council of Ministers of the People's Republic of Bulgaria.
Accommodations for attendees were in Golden Sands, a seaside resort 17 km from Varna. Shuttle bus transportation was furnished between the hotels and the meeting site. The meeting and symposia were attended by 584 individuals from 36 countries, and more than 400 papers were presented at the open working group sessions, the panels, and the symposia.