So far, we have made the problem situation explicit by identifying actors involved, their perception on the problem and their goals and criteria.

Now we finally want to know what influences these criteria. Criteria represent everything the actors consider important. So solving the problem means for them doing something that influences the criteria in a positive way.

Therefor we need to identify causal relations in our problem situation. What leads to what? Causal chains. Identifying these makes it possible to, later, in the next step, come up with solutions to the problem.