Linguistic Grammar as Dynamic Logic Johan van Benthem Abstract: Natural language is the primary vehicle of human communication. It involves a series of interlocked processes at various levels of aggregation. Proof theory and dynamic logic provide two paradigms for dealing with this variety. This paper gives an analysis of some main issues that arise in merging the two viewpoints towards this broader goal. Topics discussed include: proof as discourse, interfacing low­level fast and high­level slow systems, merging lambda dynamics and modal state dynamics, strategies that create feasible proof calculi. Overall prospects for broad 'dynamic architectures' look good.