Wallach opened the hospital with two trained nurses, Schwester (Nurse) Stybel and Schwester Van Gelder.
Van Gelder returned to her native Holland early on, being dissatisfied with the "primitive conditions" that existed at Shaare Zedek.
Stybel fled to Germany with the outbreak of World War I; when she returned, she organized a strike against the conditions at the hospital.
Wallach did not respond to her demands, and when she was unable to find other work and asked for her job back, he made her head of the laundry. "
A true nurse never abandons her patients", he told her.

In dire need of a head nurse, Wallach traveled to Europe in 1916.
He was impressed with the similar organizational structure of the Jewish Hospital in Hamburg, and asked the head nurse there if she could spare one of her staff.
The 32-year-old Selma Mayer (1884–1984), who in 1913 had been one of the first Jewish nurses to receive a German State Diploma, was recommended and agreed to travel.
She arrived at Shaare Zedek in December 1916 and worked and lived at the hospital for the next 68 years, until her death at the age of 100.

Schwester Selma was Wallach's right-hand person in the running of the hospital.
She accompanied him on house calls and stood in for him as hospital director when he was away.
She applied the German system to running the wards and cultivated a spirit of warm, personalized patient care that became the modus operandi for the hospital to this day.
Wallach opened the hospital with two trained nurses, Schwester (Nurse) Stybel and Schwester Van Gelder. Van Gelder returned to her native Holland early on, being dissatisfied with the "primitive conditions" that existed at Shaare Zedek. Stybel fled to Germany with the outbreak of World War I; when she returned, she organized a strike against the conditions at the hospital. Wallach did not respond to her demands, and when she was unable to find other work and asked for her job back, he made her head of the laundry. "A true nurse never abandons her patients", he told her.
In dire need of a head nurse, Wallach traveled to Europe in 1916. He was impressed with the similar organizational structure of the Jewish Hospital in Hamburg, and asked the head nurse there if she could spare one of her staff. The 32-year-old Selma Mayer (1884–1984), who in 1913 had been one of the first Jewish nurses to receive a German State Diploma, was recommended and agreed to travel. She arrived at Shaare Zedek in December 1916 and worked and lived at the hospital for the next 68 years, until her death at the age of 100.
Schwester Selma was Wallach's right-hand person in the running of the hospital. She accompanied him on house calls and stood in for him as hospital director when he was away. She applied the German system to running the wards and cultivated a spirit of warm, personalized patient care that became the modus operandi for the hospital to this day.
Moshe Wallach