The problem this paper deals with is the problem of how dispositional properties can have causal relevance. In particular, the paper is focused on the question of how dispositions can have causal relevance given that the categorial bases that realise them seem to be sufficient to bring about the effects that dispositions explain. I show first that this problem of exclusion has no general solution. Then, I discuss some particular cases in which dispositions are causally relevant, despite of this exclusion (...) problem. My claim is that dispositions have causal relevance in selection or recruitment processes, when they are converted into teleological functions. (shrink)