This paper considers the challenges faced by those seeking to design effective blended learning. Using a 2-year case study involving cohorts of approximately 200 students, it demonstrates how Anthony Giddens structuration theory can provide a metaframework for assisting educational designers in creating coherent blended learning experiences that reinforce intended learning outcomes. It calls for educational designers to be sensitive to both their audience and the unintended and unanticipated consequences of their actions and shows how a holistic annual review framework can reinforce or suppress emergent behaviour through unit development.