Base systematic research in this paper argues that even if there are many social work practitioners, scientists and students of the opinion that research in this field is of little use, we shouldn't be so pessimistic. Far from it, the authors are of the opinion that both intuitive and rational thinking and decision making are equally important for a practice which - in order to avoid mistakes and prejudices - must rely on "fast thinking" as well as on "slow thinking". Against this background the paper firstly works out the deficiencies of both epistemological approaches and then argues for a constructive relationship between practical and scientific thinking in social work. German and international examples of good research practice demonstrate the usefulness of a broad knowledge base in social work for practice and decision making. Finally, the paper summarizes the main preconditions which are necessary to realize a new relationship between social work practice and research.