Counterfactual constructions convey the meaning that the speaker believes a certain proposition not to hold. This article investigates the morphosyntactic composition of counterfactual conditionals and counterfactual wishes and the question of how the form of counterfactuals is related to their meaning. Across languages, there are combinations of tense, mood, and aspect morphemes that are used repeatedly in the expression of counterfactuality. I discuss the role of all three components.