In this paper I argue that a fine-grained functional hierarchy of semantically contentful categories such as Tense, Aspect, Initiation, and Process has explanatory power in understanding the crosslinguistic distribution of complex predicates. Complex predicates may involve adjunction, control, or raising, and show other variables as well. In a Minimalist framework, specific parameters cannot be invoked to allow or disallow different kinds of serial verbs, light verbs, resultatives, and so on. Instead, what variation is observed must come from the specifications of lexical items. This places a great burden on the learner, a burden which, I argue, is partly alleviated by the functional sequence