The goal of this article is to understand the syntax of Icelandic indirect causatives (ICs), especially with respect to the implicit causee. We show that the complement of the causative verb must be at least as large as a VoiceP, and that it shares some properties with active VoicePs and others with passive VoicePs. We make sense of this state of affairs by proposing that the causee, while phonetically silent, has an explicit syntactic representation, but as a φP rather than a DP. We further propose that ICs are built by stacking a second VoiceP on top of the lexical verb’s first VoiceP, and that this configuration, along with the underspecified interpretation of φP, leads to a special thematic interpretation of both the causer and the implicit causee. Our analysis suggests that there are certain core ingredients involved in building ICs—such as stacked VoicePs and an underspecified causee—but that the source of these ingredients can vary across languages and constructions, depending on the formal primitives that grammars make available to the languages more generally.