This article discusses the grammatical role played by the interpretation of an action as either intentional or accidental. It focuses on two grammatical restrictions that exhibit sensitivity to such interpretation. The first concerns so-called subject obviation, whereby, in many European languages, the subject of the subjunctive clause cannot refer to the same individual as the subject of the matrix clause. For the purpose of this article, an important property of subject obviation is that it is weakened in the case of accidental actions. The second restriction pertains to an aspectual restriction in negative imperatives and desire statements in Slavic, which disallows the perfective aspect in these constructions. As is the case with subject obviation, the aspectual restriction in Slavic is lifted when the action is interpreted as accidental. This article argues for a unified semantic-pragmatic account of the weakening of subject obviation and aspectual restriction. It also shows that this weakening of obviation and of aspectual restriction is part of a larger picture where the interpretation of an action as intentional versus accidental plays a central role.