The main ideas in the work of Hans Freudenthal (1905± 1990), the Dutch math-ematician and mathematics educator, related to curriculum theory and didactics aredescribed. Freudenthal’ s educational credo, ` mathematics as a human activity’ , isexplored. From this pedagog ical p oint of departure, Freudenthal’ s criticism ofeducational research and educational theories is ske tched and ¯ eshed out.Freudenthal’ s approaches to mathematics education, developmental research andcurriculum development can be seen as alternatives to the mainstream ` Ang lo-Saxon’approaches to curriculum theory.