After working at the Amsterdam office of the Twentsche Bank (a precursor of ABN AMRO), he opened a small accountancy practice in 1917 in his home on the Viottastraat in Amsterdam. Amsterdam was a bustling trade and investment hub for European and Asian industrialists.
He started at the Amsterdam office of Twentsche Bank (a precursor to ABN AMRO), which ultimately led him to establish a small accounting practice in 1917 from his home on Viottastraat in Amsterdam. Given its status as a major commercial and investment hub, Amsterdam attracted numerous European and Asian industrialists.