This paper presents a novel analysis of disjunction that substantially differs from previous analyses. In particular, it is argued that Japanese disjunction is not a PPI, but is derived from an adjoined alternative question. The proposed analysis is capable of accounting for why Japanese disjunction has two of the properties of PPIs (namely, wide scope with local negation and narrow scope with non-local negation), but lacks so-called rescuing effects. Further supporting evidence is provided from diachronic and syntactic data.