Updated: Apr 29, 2021
“I could have left at any time, said Eli Cohen. Zalman himself told me. Come and try intelligence work for six months. If you like it, stay, if not – you're free to do as you wish.” 
The photo above of Foreign Ministry taken in Prague, between 1949–53 of possible members of the original Mossad as we know it today. On left is Rafi Friedl hero of Slovak Jewish underground in Budapest, The third person from the left was a “cipher clerk” (Yosef Bernstein - Eilom) at the embassy middle is Reuven Shiloah (head of the Mossad), in middle is Moshe Sharett (Shertok) and to his right in back is Zalman smiling and to the far right is Ehud Avriel. In back right, behind two people is Michael Hutter.
Source: Martin Šmok, Curator, postwar segments of new permanent exhibition for the Spanish synagogue at Jewish Museum in Prague.
The following stories take place in the mid to later part of Zalman’s career, after his work in Czechoslovakia. Zalman’s diplomatic missions in Prague ended fairly abruptly, when the initially promising relations between Israel and Czechoslovakia deteriorated rapidly after Moscow reversed its attitude towards Israel. This sentiment change culminated in the expulsion of Israel’s foreign minister, Aryeh Kubovy, from Prague in December 1952 just after the Slánský trial. At this point, Zalman was still abroad, but we know very little about his work. We were, however, able to learn about some of the other people he assisted and the historical moments he was a part of towards the end of his career.
The Mossad, by its nature, has always been shrouded in mystery.
Indeed, in 2019, Shin Bet and the Mossad extended declassification of secret service documents for another 90 years, reinforcing the ongoing need for such secrecy.
Reuven Shiloah is known as the first leader of the Mossad, Israel’s counter-intelligence organization. Mossad literally means "the Institute" or the “Institute for Intelligence and Special Operations.” The Mossad was formed on December 13, 1949, as the Central Institute for Coordination, at the recommendation of Prime Minister David Ben-Gurion . Ben-Gurian appointed Shiloah as the Mossad’s first Director, a position he held from 1949–53.
Before the Mossad was established in 1949, Zalman was a member of the “Shai,” the unit within the Haganah that predated the Mossad, which was also led by Reuven Shiloah. Shai (Hebrew: ש"י, an acronym for Sherut Yediot (שירות ידיעות), lit. Information Service), was established in 1940 as the intelligence and counter-espionage arm of the Haganah. Later he was part of the collective groups that were involved in the operation called the Bericha, managed by a branch of the Mossad known as Aliyah Bet, which was the underground organized effort that helped Jewish Holocaust survivors escape post–World War II Europe to then British Mandate Palestine.
Based on a review of his records, Zalman performed a variety of different types of work during this time period, including intelligence gathering, covert and international operations, working with allied foreign intelligence services and nations that had no normal diplomatic relations with Israel and more (i.e. collecting political and economic intelligence).
In Miriam Kubovy’s rare book, called the “Wife of the Israel Minister to Prague and Warsaw,” she quotes my grandfather when they arrive in Prague during this challenging period:
"And now, said Zalman (Attaché to the Legation in Prague) as he accompanied us outside to our car, look discreetly at the house opposite... you will see a curtain move slightly. In that house they will always know when you arrive and when you leave, where you are going and whom you will meet. But don't worry and, don't think of it all: that’s the Secret (Stalin) Police of Prague you see..."
Kubovy offers further insight into life during this time period in Czechoslovakia, as the wife of an Ambassador.
One of Zalman’s many gifts was his ability to identify talent and train non-professionals. He succeeded in recruiting athletes to become professionals and similarly developed civilians into successful intelligence gathering operators. One such individual is Eli Cohen, also known as Eliyahu Ben-Shaul Cohen, who is commonly known as Israel’s most famous spy. Cohen is best known for his espionage work in 1961–1965 in Syria, where he gathered significant information that helped Israel succeed in the Six-Day War. Syrian authorities eventually uncovered his activities, captured and tortured him before sentencing him to death and publicly hanging him in 1965.
My father shared a story about how Zalman helped recruit and provide some of the intelligence training Eli received in the late 1950’s or early 1960’s, which is consistent with the supposed training period referenced in the Jewish Virtual Library. He came upon this information from a publication he read about Cohen approximately 30 years ago, but he refused to name the author or title of the publication, fearing the disclosure will compromise someone.
During my research, however, I found the same or a similar publication online. The document is called “The Eli Cohen Files Part II: The Making of a Masterspy” By Wesley Britton. It describes Cohen’s years in Israel from 1956 through his recruitment and eventual deployment in Syria. The article also analyzes his contributions and achievements and explores myths about these accomplishments.
Cohen’s trial testimony included his memories of being recruited into Israel’s counter-intelligence. Cohen recalls “one day a man named Zalman came to see me. He told me that they had kept an eye on my work and found that I was suited to a more responsible task. He asked me if I was willing to work for Intelligence and to go to Europe or an Arab country . . . I told him that I had just married, and didn't have the urge to travel. My wife was a nurse before we got married, but she had quit work when she became pregnant and I had to work overtime. (Ben-Hanan 108).”  Thus, this publication appears to support my father’s memory of Zalman’s involvement in Eli Cohen’s recruitment and training.
 The Eli Cohen Files Part II The Making of a Master Spy by Wesley Britton http://www.spywise.net/wbf/cohen3.pdf
 Ben Gurion wanted to centralize and improve cooperation between Israel’s existing security services, such as the army's intelligence department (AMAN), the Internal Security Service (Shin Bet), and the foreign office's "political department." In March 1951, the Mossad was reorganized and made a part of the prime minister's office, reporting directly to the prime minister.
 http://www.spywise.net/wbf/cohen2.pdf [site no longer available]