Augustyn Träger (25 August 1896 – 22 April 1957), codenames Sęk (Knot) and Tragarz (Porter), was a Polish-Austrian soldier during World War I and an intelligence officer in interwar and German-occupied Poland. Along with his son, Roman Träger, he played an important role in obtaining intelligence on the German V-1 and V-2 missiles which were being tested on the island of Usedom in Pomerania. He passed the information along to the Polish resistance organization Home Army, which then passed it on to the Allies in London. This led to the Allied bombing of Peenemünde in Operation Hydra in 1943.