Nils Arbohm (1905-1997).
Educated as an architect at KTH in 1927, worked with Ivar Tengbom for five years. After meeting at KTH, Ahrbom & Zimdahl started their architectural office in 1927.
One of their first joint assignments was the school at Sveaplan in Stockholm (today 'Socialhögskolan') in 1931.
Ahrbom held the professorship in architecture at the Royal Institute of Technology in Stockholm in the years 1942-63.

Helge Zimdal (1903-2001)
Graduated from the Royal Institute of Architecture in Stockholm in 1927 and at the Stockholm School of Art in 1930. He attended the Stockholm exhibition in 1930 with furniture and textiles, the furniture partly in collaboration with Carl-Axel Acking. At KTH he had met Nils Ahrbom, with whom he ran the architectural office Ahrbom & Zimdahl during the years 1927-1951.

When Helge Zimdahl became Professor at Chalmers in 1951, he took away 'h' in his last name and became Zimdal after that.