Summary: Behaviour Monitoring and Interpretation is a new field that developed gradually and inconspicuously over the last decades. With technological advances made at the sensory level and the introduction of ubiquitous computing technologies in the nineties this field has been pushed to a new level. A common methodology of many different research projects and applications can be identified. This methodology is outlined as a framework in this paper and supported by recent work. As a result it shows how BMI automates ethology. Moreover, by bringing in sophisticated AI techniques, it shows how BMI replaces a simple behaviour-interpretation mapping through computational levels between observed behaviours and their interpretations. This is similar to the way of how functionalism and cognitive sciences enabled new explanation models and provided an alternative approach to behaviourism in the early days of AI. First research results can be finally given which back up the usefulness of BMI.