Doing Argumentation Theory in Modal Logic Davide Grossi Abstract: The present paper applies well-investigated modal logics to provide formal foundations to specific fragments of argumentation theory. This logic-driven analysis of argumentation allows: first, to systematize several results of argumentation theory reformulating them within suitable formal languages; second, to import several techniques (calculi, model-checking, evaluation games, bisimulation games); third, to import results (eminently completeness of axiomatizations, and complexity of model-checking) from modal logic to argumentation theory.