This paper reviews the rapidly developing field of epigenetics, providing an accessible explanation of the key ideas and some illustrative examples of work in the field. Although very much a biological discipline the implications of the developing knowledge in this area are very significant for educational psychologists and this paper aims to provide an introduction to what is becoming a very significant shift in how people think about learning and development. Understanding the processes that underlie epigenetic change and the research that the new knowledge is based on will be important for educational psychologists in order to understand this important developing area of thinking about development and learning. Consensus is growing that intergenerational transmission of epigenetic changes are a reliable phenomenon, establishing the principle of the inheritance of acquired characteristics. This contrasts starkly with models of biological determinism and provides a new way of thinking about educational and societal change.