On 1 May 1967 Dr. J elle Zijlstra was appointed President of De Nederlandsche Bank, after an already eventful career. Following a brief spell as Professor of Economics at the Free University of Amsterdam, he began a lengthy period of ministerial service in 1952. During his cabinet years, he devised a concept which became known in the Netherlands as the' Zijl- stra norm', and which was aImed at keeping the Government's financial deficit in check. He concluded his active political career .as prime minister in 1966-1967. Dr. Zijlstra's career as a politician and central banker covered a period of nearly 30 years during which the economic scene in the N ether- lands and in the world underwent wide cyclical ups and downs and impor- tant changes of a more long-lasting nature. Successful economic recovery after the Second World War was followed by a period of rapid and rela- tively stable economic growth. However, as early as the 1960s the condi- tions for the maintenance of equilibrated expansion became less secure. These conditions were further impaired in the 1970s partly as a result of important shocks, such as the oil crises.