Many professions involving relational work as an essential component – such as nurses, social workers and psychotherapists – are currently challenged by a growing demand on so-called “evidence-based” methods. In the debate, professional practioners from these fields have repeatedly voiced the complaint that there are crucial aspects of knowledge involved in their professions that do not fit into this paradigm. Their Professional abilities, they claim, include a kind of knowledge that might not be “scientific” or “evidence-based”, but is still essential to what they do. This article will discuss how this “practical knowledge” can be approached using resourses from Heidegger’s phenomenological appropriation of Aristotle.