The “Shai“ (Sherut Yediot), which operated in the 1940s in the Jewish community of Mandatory Palestine, served as the foundation for Israel's intelligence apparatus. 

In June 1948, under Prime Minister David Ben-Gurion's directive, the “Shai“ was dismantled. Its commander, Isser Be'eri, announced the creation of three new organisations : “Shin Mem“ (Military Intelligence Service), “Makhatz“ (later the Israeli Security Agency or Shin Bet), and “Da'at”  (which later became the Mossad).

1949 – “Shin Mem” was transformed into the Military Intelligence Directorate (“Aman”) of the IDF. Unit 10 (later Unit 504) was established to gather intelligence through agent recruitment and prisoner interrogation (HUMINT). The Mossad was also created to coordinate intelligence efforts, led by Reuven Shiloah.

1950 – The Shin Bet was separated from the military, becoming a civilian agency under the Ministry of Defense (later under the Prime Minister’s Office), responsible for countering hostile activities within Israel, including espionage and counterterrorism.

1951 – “Da’at” was placed under the Mossad, becoming its operational arm for covert activities abroad. 

1952 – “Nativ“ established to maintain connections with Jews in Eastern Europe and the Soviet Union.

1953 – The Intelligence Directorate (“Aman”) became an independent branch of the IDF General Staff.