Despite being of crucial importance in Education, the issue of motivation has been only very recently explicitly addressed in Intelligent Tutoring Systems (ITS). In the few studies done, the main focus has been on motivational planning (i.e. how to plan the instruction in order to motivate the student). In this paper we argue that motivation diagnosis (i.e. how to detect the student's motivational state) is of crucial importance for creating `motivating' ITSs, and that more research