The Servizio Informazioni Segrete was the intelligence service of the Royal Italian Navy. SIS was instrumental in moulding Italian Army's operations during the Second Italo-Ethiopian War and the Battle of the Mediterranean, primarily due to its cryptanalysis successes and undercover operations.

The Italian Military Information Service was the military intelligence organization for the Royal Army of the Kingdom of Italy from 1925 until 1946, and of the Italian Republic until 1949. The SIM was Fascist dictator Benito Mussolini's equivalent to the German Abwehr. In the early years of the war, the SIM scored important intelligence successes. Rommel’s successful military operations in North Africa in 1942 were substantially facilitated by the SIM through the securing of the U.S. Black Code used by Colonel Bonner Fellers to communicate plans for British military operations to his Headquarters in Washington.