This article seeks to contribute to recent theorizing around the concept of powerful knowledge. I begin with a discussion of the current use of the term in both academia and the wider institutional environment of schools. I then give a detailed account of its origins in social realism before exploring different iterations of the concept in recent academic work. The second half of the article seeks to develop the idea of 'power' in powerful knowledge by engaging with the criticisms of philosopher John White. I do this by bringing in the philosophical work on the concept of power offered by Peter Morriss. I conclude that Morriss' analysis of power can help reveal why 'power' is best seen as a disposition to effect certain ends. I suggest that this helps resolve some of the concerns of White and provides a template for how to think about powerful knowledge going forward.