This special issue of Journal of Solid State Electrochemistry contains a selection of manuscripts out of over 70 oral and poster contributions presented at the Workshop on Electrochemistry of Electroactive Materials (WEEM-2009) that was held in Szczyrk, Poland, on 14th to 19th July 2009. The event was sponsored by the International Society of Electrochemistry and supported by the Faculty of Chemistry, University of Warsaw, Poland. The event attracted over 80 participants from many countries from all over the world. It was organized by the Local Committee (headed by P. J. Kulesza, M. Skompska, and M. A. Vorotyntsev) together with the Scientific Committee (L. M. Abrantes, V. Z. Barsukov, C. Deslouis, J. Heinze, A. R. Hillman, G. Inzelt, P. J. Kulesza, O. A. Petrii, P. G. Pickup, M. A. Vorotyntsev), and Advisory Board (D. Aurbach, V. M. Mirsky, O. A. Semenikhin, M. Skompska, V. Tsakova, C. Visy).

The series of conferences on electrochemistry of electroactive materials are organized periodically every 3 years in the form of workshops, bringing together internationally recognized experts as well as many younger researchers in the area of mixed (electron ion) conducting materials that include numerous systems of diverse chemical nature such as redox or electronically conducting polymers, polynuclear mixed-valence inorganic systems, or intercalation materials typically in contact with liquid or semi-solid electrolyte solution. The last workshop in Szczyrk, Poland (2009), has followed the previous successful events in Repino, Russia (2006), Bad Herrenalb, Germany (2003), Poraj, Poland (2000), Dourdan, France (1997), and Uzkoye, Russia (1995). All these events were sponsored by the International Society of Electrochemistry, and some of them also by NATO, European Section of Electrochemical Society, as well as national scientific organizations.

The conference comprised a welcome session on Wednesday (July 14, 2009), two plenary sessions dedicated to Professors Juergen Heinze (University of Freiburg, Germany) and Zbigniew Galus (University of Warsaw, Poland) as well as six half-day sessions in the remaining days. The meeting provided an informal forum for discussion of new results and major achievements in the electrochemical science and technology of electroactive materials. Typical session topics covered fundamental and applied aspects of fabrication and characterization of novel systems, experimental and theoretical studies of their properties, molecular mechanisms and dynamics of charge propagation, and electrochemical processes occurring in these materials. Traditionally, a specific feature of the workshop was the absence of a rigid timetable with assumption that only overall duration of each session was fixed, and a significant part of the available time was left for intensive discussions moderated by the session chairpersons. Informal discussions were often continued during breaks and even during hot summer evenings and nights.

Szczyrk itself is a picturesque mountain resort lying in the Silesian Beskid Mountains located in the southern part of Poland. The meeting was organized in the conference–recreation centre located at the bottom of Skrzyczne—the highest peak of the Silesian Beskid Mountains. I am indebted to local staff (L. Adamczyk, M. Skompska, M. A. Vorotyntsev, K. Miecznikowski, K. Maksymiuk, A. Michalska, and I. Rutkowska) for their help before and during the meeting as well as for their efforts to make the stay of participants in Szczyrk pleasant and comfortable.