In this article, the conceptual instrument that pragma-dialectical argumentation theory offers is elaborated for the analysis and evaluation of problem-solving discussions. The elaboration is aimed expressly at taking into account the discussion character of the discourse, in order to show how the developing process evolves and what the obstacles are therein. In addition, it focuses expressly on the verbal behaviour of the participants and on showing how this behaviour controls the evolving process. The analysis and evaluation is based on insights (...) and methods of conversational analysis and discourse analysis. One fragment of a problem-solving discussion is analysed and evaluated. (shrink)