The verbal suffix -kan in acrolectal Indonesian gives the appearance of being a homonymous form with multiple functions. In many sentences the suffix seems to be a causative morpheme; in others it appears to be an applicative affix, while in yet others it seems to be an object marker. We show that these functions are in fact predictable if -kan is a derivational morpheme affecting the argument structure of the verb to which it is affixed. We argue that the role of -kan is to indicate the syntactic licensing of an argument in the argument structure that is not licensed syntactically by the base verb. Thus, the distribution of -kan provides evidence that there exist linguistic generalizations that need to be stated with respect to a distinct level of argument structure rather than with respect to such syntactic levels as S-Structure and Logical Form.