Over the past decade, design experimentation has become an increasingly accepted mode of research appropriate for the theoretical and empirical study of learning amidst complex educational interventions as they are enacted in everyday settings. There is still a significant lack of clarity surrounding methodological and epistemological features of this body of work. In fact, there is a broad variety of theory being developed in this mode of research. In contrast to recent efforts to seek a singular definition for design experimentation, I argue that methodological and epistemological issues are significantly more tractable if considered from the perspective of manifold families of theoretically framed design-based research. After characterizing a range of such families, I suggest that, as we deliberate on the nature of design-based research, greater attention should be given to the pluralistic nature of learning theory, to the relation between theory and method, and to working across theoretical and methodological boundaries through the use of mixed methods. Finally, I suggest that design-based research-with its focus on promoting, sustaining, and understanding innovation in the world-should be considered a form of scholarly inquiry that sits alongside the panoply of canonical forms ranging from the experimental, historical, philosophical, sociological, legal, and interpretive.