This paper deals with the question of what should be the focus of measurement in a competency-based teacher education program. Two modes for measuring teaching competency, product measurement and process measurement, are contrasted and discussed. Product measurement focuses on changes in pupil behavior brought about by the teacher while process measurement focuses on the teaching act itself. Since there is little research evidence that causally links teacher behavior with pupil behavior, the simultaneous use of both product measurement and process measurement is advised. (Author)