ABSTRACT
The preceding chapters in this book describe specific methods of diagnostic assessment. They are all efforts to develop a scientific model of how to assess individual competence. There is a hope, which I share, that diagnostic assessment can improve educational practice. The current chapter is directed toward a larger issue: To what extent is the goal itself realistic? In examining this issue I, of course, comment on some of the individual chapters. However, my goal is not to identify the best approach; it is to identify ways in which diagnostic assessment systems can be designed, and to consider where particular designs are most useful.
