This paper examines the concept of 'powerful knowledge' and provides new perspectives on an important emergent theory for education. We claim that the key to attaining powerful knowledge is 'epistemic access' to the discipline, which is access of the generative principles of knowledge creation. We draw on 15 years teaching and researching a university science programme in which undergraduate ecology students are trained as researchers during the 3 years they attend university. Hence, there is close alignment between teaching students to do research and powerful knowledge. In addition, it has been suggested that the 'power' in powerful knowledge is realised in what is done with that knowledge, that its purpose is social since it allows the holder to make a better contribution to society. We argue that in addition to such an aspirational 'outcome', it can be part of the "process" of education and early acquisition of powerful knowledge can influence all subsequent formal and informal learning experiences as the student progresses though university. A model for powerful knowledge is presented in which there is the "possibility" of powerful action after graduation, but this remains in the theoretical realm while there is very little empirical evidence supporting such a hypothesis for ecology students. Powerful action also questions the limits of responsibility for a teacher.