This issue of the "Journal of Curriculum Studies" presents a symposium on the recent work of Michael Young. Contemporary curriculum theory has little specific to say about how knowledge is selected, organized and transformed into curriculum content for teaching and learning. Over the last two decades, Young has taken a rather different course from the Neo-Marxist tradition of critical curriculum theory of which he is one of the primary founders. Such a tradition, Young now observes, is built upon "over-simplistic" social constructivism that reduces knowledge to interest, ideology or standpoint. This special issue presents six commentary essays written by a distinguished panel of international scholars from different countries across the globe: David Baker (USA), Zongyi Deng (Singapore), Ursula Hoadley (South Africa), Ulf Lundgren (Sweden), Elizabeth McEneaney (USA) and Leesa Wheelahan (Canada). Also included is a response paper to these six essays from Michael Young (UK). In the first paper, Hoadley (2015) discusses what should be made of Young's recent work in view of South African curriculum reform of which Young has long been a consultant. The second paper (Wheelahan, 2015) extends the relevance and significance of Young's recent work to vocational education and training (VET) where the neglect of knowledge in curriculum is evident most strongly. The third paper expounds on the significance of Young's recent work with reference to contemporary curriculum theory. The fourth paper Draws on Schwab's "the structure of the disciplines" thinking and the German "Didaktik" tradition, where Deng (2015a) extends and enriches the conversation concerning Young's (2013) knowledge-based approach to curriculum. In the fifth commentary paper, Lundgren (2015) takes issue with Young's (2013) notion of a crisis in curriculum theory and his resolution to the crisis. Finally, McEneaney (2015) questions Young's perspective on the internet and his insistence on the role of formal schooling in transmitting powerful knowledge, with respect to his knowledge-based approach to curriculum.