 When one meets a problem in formalizing certain aspects of reasoning via a given formal system (e.g., SDL), one may diagnose the situation in two different ways: as caused by a lack of expressive power in the formalism, one that can be remedied by augmentation, or as a fundamental problem with the initial formalism itself calling for modification or replacement of the initial formalism. In the present section, we survey some attempts to revise the foundations of deontic logic, in view of specific puzzles related to SDL and its extensions.