This chapter introduces The Linnaeus University Centre for Intermedial and Multimodal Studies (IMS) and presents the theoretical and institutional legacy of its founder Lars Elleström to the field of intermedial studies. We present central aspects of his theoretical framework and we discuss how concepts such as the media product, the media modalities, and media transformation respond to central challenges in intermedial theory. Also, we demonstrate how they have been applied in intermedial analysis at IMS and internationally as a flexible framework that can be connected with approaches to media. Finally, we put forth some of the challenges to Elleström’s framework as a media-centered model of communication and hint at possible ways to meet these.