Adult learning is described as learning undertaken by adults in natural educational settings as opposed to the experimental settings often undertaken in psychological research on learning. As such, the theory and research on adult learning referred to in this article primarily draws on applied educational research reported in adult education journals. Much of this research is informed by psychological and social research and theory, and this is acknowledged in each of six adult learning themes outlined in this article. These themes are self-directed learning, experience and learning, learning styles, the development of identity in the adult years, intellectual and cognitive development, and transformative learning. While these themes focus on adult learning in a general sense, our understanding of adult learning also needs to be seen in relation to the context in question; contexts such as health, the third age, indigenous knowledge, literacy and numeracy, the environment, disability, community education, gender equity, race, and migrant and refugee education. The literature on adult learning offers very few prescriptive bridges linking research, theory, and practice. This is partly because there are competing theories posing different questions and offering opposing interpretations of research findings, but it is also because the purpose and function of education and learning is a contested field. In these circumstances the best approach for practitioners is to interrogate and improve their practice through engaging with research findings, competing models, and competing theories. In this way they are aware of the variables at play and can formulate practices that are consistent with their educational aims and purposes. The link between research, theory and practice is conceptual rather than prescriptive, with practitioners interrogating and improving their practice by engaging with the issues and the competing claims of theory and research.