In this paper we discuss practice-based research. This type of research meets not only the traditional scientific research standards but also standards relating to its usefulness in educational practice. It is a first attempt to connect the separate worlds of science and practice. Studying review articles we abstracted criteria and standards for conducting practice-based research. These criteria were presented to a dozen (assistant) professors and after some reformulations we consulted a variety of experts and analysed four cases. The main conclusion of this study is that criteria for feasibility in practice and science should be seen as competing values with their own optimal mix in particular situations.