Buddy diving just before and after the Second World War. After the invention of the "aqualung" by Cousteau and Gagnan, the first commercially underwater breathing apparatus became available for sale for sporting purposes in the late 1940s. As the new sport of scuba diving rapidly expanded through the 1950s, several sporting organisations—notably the YMCA—began programmes to train swimming enthusiasts in this new aquatic pastime, and began to codify what they believed were proper practises for this expanding sport. The YMCA considered the buddy system a useful corollary to the "never swim alone" rule of their swimming and lifesaving programmes. Cousteau himself independently
Jacques Cousteau usually spoke English) and with French soldiers in North Africa (under Admiral Lemonnier), Jacques-Yves Cousteau (whose villa "Baobab" at Sanary (Var) was opposite Admiral Darlan's villa "Reine"), helped the French Navy to join again with the Allies; he assembled a commando operation against the Italian espionage services in France, and received several military decorations for his deeds. At that time, he kept his distance from his brother Pierre-Antoine Cousteau, a "pen anti-semite" who wrote the collaborationist newspaper "Je suis partout" ("I am everywhere") and who received the death sentence in 1946. However, this was later commuted to a life sentence,