This article addresses why and how to support faculty working with student writers on multimodal projects at all levels across the disciplines. The authors argue that faculty need support in the design, implementation, and assessment of multimodal projects so that students are better positioned to transfer writing knowledge and (multimodal) composing practices throughout and beyond their undergraduate careers. Building upon recent scholarship on transfer and multimodality, in concert with Anne Beaufort's (2007) conception of knowledge domains from which successful writers draw, a framework is presented for implementing theory-driven WAC faculty development in multimodal assignment design. The authors conclude by summarizing faculty responses to engagement with these theories at a workshop session, describing multimodal assignments created by faculty, and sharing an assignment design guide that scaffolds the development of multimodal projects.