How a diagnostic device is used also relates to what sort of manager of change you are (in terms of the change manager images discussed in Chapter 2). One option consistent with the change manager as director is to use diagnostic tools to build up your own knowledge base and confidence about what needs to change by using models that specify relationships among variables and pinpoint where change is needed when things are not going well. This chapter provides a number of such models that depict the connections between organizational variables (through the use of boxes, lines, and arrows, etc.). These models may be seen to engender a level of confidence about the desired outputs that will be produced following change interventions that focus on the identified variables and their interrelationships (see, e.g., Nadler and Tushman's congruence model).