1. 'One-foot walking': what is teaching?Quick skimming through didactics bibliography reveals some non-homogeneous criteria about this matter. There are the 'generalists' - who focus on teaching 'practice'- and the 'specific/disciplinary' ones -who focus on teaching 'contents'-. Therefore, the real problem is not this, but their notorious inability for account teaching practice as a whole. As these two approaches seem to me appropriate and reasonable, but unsatisfactory if they are separately taken (as if we should try to walk only on one foot), I suggest moving our epistemological regards to the idea of an epistemological double-root conveying teaching practice. I shall try to argue for the existence of two simultaneous and mutually integrated epistemological sources for teaching practice, and its implications for teaching researching betterment (both, practical and academic research). 2. The practice and the practitioner: the epistemology of practice Epistemology of practice (Schön, 1992) refers to how practice may be understood. Therefore, we must avoid poor understandings on teaching practice as some instrumental practice where what is taught means mere blanks to be filled. In the extent that teaching practice is more than speaking pupils about history or chemistry, its practical nature introduces a necessary subjective perspective in order to seize 'action' features of teaching. Teachers do what they do because they feel they must do it in this way and for some precise reasons. This is practice. They are acting subjects of practice. However, teachers always teach something, so the knowledge they teach belongs to practice, a very part of teaching practice. Teachers always choose what they want to study and teach, meaning history, modern history, Marxist modern history… at school, or at University… Reasons, intentions and modes of teaching always involve both the teacher and the subject knowledge. Studies on epistemology of practice are to be extended up to these 'new' boundaries, in the framework of a double epistemological perspective of teaching practice. 3. Teaching, learning and knowledge: what epistemology?It seems to be undeniable that different people are differently linked to knowledge. Historians -for instance- research and write historiographic knowledge. They build their mimetic version of the past, stated on historical epistemological features, personally arranged by each one according his 'practical reasons' for doing history. This is history. Lately, history teachers partially read, partially learn and partially teach about historiographic knowledge… as they understand it and as they feel they must teach it, because their practical reasons to do so. This is teaching history. Finally, pupils study (when it arrives) history: they memorise, repeat, learn, handle, or whatsoever it should happen (I mean, even pervert it) between history and them. This is real world.This means that not only action and subject theories (Baudouin, 2001) are bound to improve our understandings on teaching practice but also reading and interpretation theories (Ricoeur, 1985; Certeau, 1975) must be reconsidered in order to come over some very narrow perspectives on knowledge related to teaching practice. Once again, double epistemological perspective on teaching practice will enrich both, current understandings on teaching 'practice' and also on teaching 'contents'. 4. The ontological partnership between teaching practice and academyClassical authors usually consider that teaching practice and academy share knowledge (meaning mostly 'information'), as producers and spreaders do. Currently, both practical and speculative research on didactics (i.e. teaching theory) are committed to searching on the close relationship between practices (teaching, researching, and other kinds of action), thinking (language and discourse) and the nature of knowledge. As a teacher-researcher on history and didactics of history, accountable for some fructiferous and long-termed practical research processes, I am indeed able to support that encouraging practical and academic research on teaching practice from a double epistemological framework means worthy enhancement. We shall -be sure- become aware of unnoticed old partnerships.