1 For the history of the historiography of sciences Transversal: International Journal for the Historiography of Science is pleased to announce its first issue. Thanks to the efforts of a group of collaborators from many countries, a project conceived, discussed and matured over a long period of time, now becomes a reality with the publication of this first issue. So it is very important to remark that this project has had the support and participation of scholars from more than 15 different nationalities. Specifically for this first issue more than 70 researchers, among authors, editors and referees, from different parts of the world were mobilized. We would like to express our deepest appreciation for the support received, but above all for their believing in this project. Without such cooperation and support this project would not be possible. This journal intends not to be just another journal. Transversal does not fit in and does not add up to the incredibly large set of new journals that have emerged in recent years as a result of the technical facilities and low costs offered by online versions of academic journals. Instead of this, for a long time, we discussed the editorial difficulties encountered by the area and the lack of an academic journal dedicated specifically to this subject. Before any technical facility, what moves us is the need to express this area of research. Thus, the main aim of Transversal is precisely to aggregate an international community around dialogue, analysis and criticism of the historiography of science. For, we believe, the expression “historiography of science” in the title of this journal relates to an evidence that we should address historically and critically, that is, the evidence that the writing of the history of science has in itself a history. One can see this historicity of the writing of the history of science from Condorcet to current social studies of sciences; from Auguste Comte to Thomas Kuhn; from Paul Tannery to I. Bernard Cohen; from Pierre Duhem, Georges Sarton and Aldo Mieli to the historical French epistemology of Gaston Bachelard, Georges Canguilhem and Alexandre Koyré; from Léon Brunschvich and Émile Meyerson to the strong program of the School of Edinburgh; from Ludwik Fleck to Michel Serres; from Edgar Zilsel and Marshall Clagett to Paolo Rossi and Joseph Agassi; from Richard Westfall to Pietro Redondi; from A. Rupert Hall to Steven Shapin; from Hélène Metzger-Bruhl to Alistair Crombie; from Marie Boas Hall to Simon Schaffer; from Michel Foucault to François Delaporte; and within all of these individual and collective trajectories and paths is the historicity of an area of reflection on science which is drawn and founded on the field of history. But it is not a question of valuing here exclusively “authors” and “works”. The “places” of production of knowledge is undoubtedly fundamental to reconstitute not only the supporting materials used to structure this field, but also for the formations (institutional, sociological, intellectual and theoretical) to which their actors were subjected. In the same way, the privileged vectors of its diffusion are fundamental, in particular the journals that help to structure, promote and create, little by little, the awareness and identity of a disciplinary field. Also the associations, societies and meetings (national and international) responsible for organizing researchers from different backgrounds around common patterns and problems, thus building a sense of intellectual community. Finally, it would be necessary not to isolate the writing of the history of the sciences from the work carried out in other historiographies: art, technics and technology, society, culture, economy, etc. We understand that it is in the limits of these issues that we could define a historiography of the sciences. Now, this description necessarily leads us to define the historiography of the sciences as an essentially transdisciplinary field. Although historiography of science is a sub-discipline of History, we construe this subject broadly to include analysis of the historiography of science produced by the history of science, philosophy of science and related disciplines. By focusing its analysis on the different historical, social and epistemological implications of science, historiography of science is a transversal knowledge with respect to the production of science, hence the name of this journal. In order to accomplish its purpose, Transversal discusses historical, theoretical, conceptual and methodological aspects of the 2 different themes, works and authors present in this tradition, quoted previously, as well as the new approaches in the recent historiography of science. Last but not least, we chose to start this journey with a special issue dedicated to Ludwik Fleck’s work, an author that in different perspectives synthetizes the aims of this journal. To understand the whole of the scientific activities involving theories, experiments, laboratories as well as its social, historical and philosophical implications, Fleck used the expression “science of the sciences” (Fleck, 1986 [1946], 127). In a sense, the historiography of science as conceived here also has a similar target searching to reflect the science as a whole by means of the critical analysis of its historical, social and scientific aspects as well as its epistemological foundations. This special dossier Ludwik Fleck would not exist without the hard work of the organizers – as well as the support of their institutions – Paweł Jarnicki (Project Science Foundation, Poland) and Sandra Lang (Ludwik Fleck Zentrum, Switzerland). We would like to thank both of them. In special, Paweł Jarnicki for his leadership in this process. Editors-in-chief on behalf of the Editorial Board, Mauro L. Condé – UFMG Marlon Salomon – UFG Reference Fleck, Ludwik. “Problems of the science of science”. [1946] In. Cohen, Robert; Schnelle, Thomas (eds.). Cognition and fact: materials on Ludwik Fleck. Dordrecht: Reidel Publish Company, 1986.