A record of two lectures delivered before industrialists of the Groupement Interprofessionnel des Industries de la Région Est de Paris on 9 December 1959. Pierre de Latil explains the fundamental principles of jet propulsion and rocket mechanics to a non-specialist audience. Jean Rivoire then surveys the geopolitical competition between the United States and the Soviet Union in space, reviews British and French programs, and examines the economic opportunities for French industrialists in the growing rocket industry.