This paper is divided into two main sections that cover the theory and practice of metadata application profile development in Australian education and training. A range of historical and theoretical perspectives are discussed with emphasis upon the fact that there exists scope for a variety of interpretations as to how best to develop and/or express an application profile. Through providing summaries of a selection of Australian initiatives that span some ten years it is demonstrated that developing clarity about business requirements can be seen as the most important step in the process. In this broad historical context it is also highlighted that both theory and practice inform each other. From the diversity in requirements it is clear that one standard, one schema, or one application profile is not sufficient in the diversity of learning, education, training, and research contexts.