This paper investigates the scope of modal categories. While it is hypothesized in many linguistic theories that different modal categories have different scope, there are only very few systematic studies that show differences. The language of investigation is Japanese, which has grammaticalized all cross-linguistically relevant modal categories and has a strict and transparent head-final structure, which is conducive to the study of scope. The results show that different modal categories indeed have different scope. However the scope properties of all modal categories do not all perfectly align to form a “clean” hierarchy. These problems can be solved if one distinguishes between ‘active’ scope (i.e. the categories some category can take scope over) and ‘passive’ scope (i.e. the categories some category can take scope under), and separates volitional (mainly deontic and boulomaic) from non-volitional (mainly epistemic and evidential) modal categories.