Mezirow's Transformative Learning Theory proposes that learning in adulthood involves transforming one's meaning structures through critical reflection on assumptions and discourse. The theory defines transformative learning as using prior interpretations to develop new interpretations to guide future actions. It involves critically reflecting on content, processes and premises of beliefs and revising one's worldview through perspective transformation. Key aspects include meaning making, meaning schemes and perspectives, ideal conditions for discourse, and the adult educator's role in facilitating transformative learning.