The pressure to innovate has become pervasive. Both inside and outside the architectural profession we are increasingly pressed by the quest for the new; by an innovation imperative. But what does 'innovation' really mean for architecture? Predominantly framed in terms of technological invention, economics and consumption, the notion of innovation is often problematically applied to the arts. Design and creativity are widely considered as drivers within innovation economies, but how can architects understand and approach the imperative to innovate meaningfully, ethically and on their own terms? Suggesting a process that is fundamentally emergent, collective and environmentally situated, "The Innovation Imperative" explores architectural innovation in terms of the production of vitality. Emphasising attention to ways of doing as key to innovation, this title of "AD" brings together historical perspectives with a range of leading provocative, emerging approaches to architectural practice that together offer fresh insight into the often vague and ubiquitous atmospheres of innovation-speak. Ultimately, this issue asks how an emphasis on vitality might offer a more nuanced understanding of the aesthetic value and ethical know-how intertwined within innovative architectural endeavour.Contributors include: Mario Carpo, Oron Catts and Ionat Zurr, Jondi Keane, Brian Massumi, Leon van Schaik, Michael Weinstock, and Gretchen Wilkins and Liam Young.Featured architects and designers include: Arakawa and Gins, Eva Franch i Gilabert, Greg Lynn, MOS (Michael Meredith and Hilary Sample), Francois Roche, Veronika Valk and Vergelabs.