Achievements of the East European Socialist countries in computing -although considerable- remained little known in the West until recently. Retarded by devastations of war, economic weakness and very different levels of national science, computing ranged ‘from little to nothing’ in the 1950-s. However, full-scale collective cooperation with the USSR based on principles of equal rights and mutual assistance was aimed at increasing of common creative power. Centralised planning and ability to concentrate efficiently national resources on priority issues, state support for science and progressive educational system accessible for everybody played decisive role. The progress was impressive. Some (GDR) reached world’s level in science and engineering such as some (in Hungary) – advanced computer education, programming and efficient usage and some (in Bulgaria, Cuba) starting “from zero point” turned into reputable manufacturers. In 1970-1990, 300,000 people as the united team of eight countries jointly designed and produced advanced family of compatible computers ES. Given general review also displays some important technical and organisational details.