Business simulations are composed of a (SD-)model which represents the complexity and dynamics of business structures and concepts. Within a simulation the participants can make decisions to control the modeled enterprise. A business simulation can make the interdependencies between the different activities within an enterprise transparent to the participants. From an economical perspective the success within a business simulation can be measured by a set of specific core variables. From an educational perspective the structure of the cognitive system which is responsible for the economical success is relevant. A subsequent aspect refers to the possibilities to support the elaboration of the mental model during the activities within a business simulation. Furthermore in the context of web-based learning environments there is the issue how to foster self-regulated learning processes. A prerequisite for an effective feedback which supports learning is a continuous diagnosis of the problem solving process, in particular the diagnosis of the information-retrieval and decision-making processes. This paper describes the basic concept of the diagnostics within a prototype of a web-based business simulation called solarSYDUS. Besides the SD-model this simulation contains a component for recording information-retrieval and decision-making processes during the simulation for analyzing problem solving behavior.