International Symposium on Plasma Chemistry (ISPC) is a biannual conference which was initiated in 1973 in Germany (ISPC 1). Since the last ISPC 24 in Naples, Italy (2019), ISPC 25 was originally planned for 23–28 May, 2021. However, due to the COVID-19 pandemic, ISPC 25 has been postponed first time in the ISPC history. At last, ISPC 25 was held in the beautiful and historic city of Kyoto, Japan at Kyoto International Exhibition Hall Miyako Messe. The conference was chaired by Professor Takayuki Watanabe from Kyushu University and Professor Satoshi Hamaguchi from Osaka University, and Tomohiro Nozaki from Tokyo Institute of Technology as General Manager.

ISPC 25 welcomed 563 attendees from 35 countries. About 80% of attendees are from Japan (180), South Korea (62), Germany (50), USA (38), France (27), Belgium (24), Canada (23), and The Netherlands (18). A total of 465 oral and poster presentations were delivered, including the 2 Plasma Chemistry Award lectures, 5 Plenary Speaker lectures, 22 Invited Speaker lectures, 121 regular oral presentations, 274 posters, distributed over the 12 scientific and application topics. There were unavoidable cancellations due to quarantine restrictions or entry control related to COVID-19. The 2 day Summer School preceding the symposium welcomed 75 attendees and 5 lecturers at Kyoto Garden Palace.

The Plasma Chemistry Award, the highest recognition bestowed by the International Plasma Chemistry Society (IPCS) for lifetime achievements in the field of Plasma Chemistry, was awarded to Dr. Anthony Murphy from CSIRO Australia for 2021 and Dr. Francoise Massines, CNRS, France for 2023. Professor David Graves from Princeton Plasma Physics Lab and Princeton University, USA and Professor Mounir Laroussi from Old Dominion University, USA were elevated to the rank of IPCS Fellow (FIPCS).

The Young Investigator Awards 2023 were given to Dr. Jacopo Profili from University Laval, Canada and Dr. Yaolin Wang from University Liverpool, UK. Oral presentation Gold Medal Award was given to Yuki Takemoto from Kyushu University, Japan, and five Silver Medal Awards to Binbin Xia from University Sydney, Australia, Calum Ryan from Eindhoven University of Technology, The Netherlands, Antoine Herrmann from University of Montréal, Canada, Xiaozhong Chen from Tokyo Institute of Technology, Japan, and Simon Kreuznacht from Ruhr University of Bochum, Germany. Poster presentation Gold Medal Award was given to Jun-Jie Qiao from Chongqing University, China, and three Silver Medal Awards to Alexander Alfred Zyla from Technical University of Dresden, Germany, Yuxi Xiao from Southern University of Science and Technology, China, and Minseok Kim from University of California, Riverside, USA.

The ISPC 25 reception was held at Nijo-jo Castle. We were able to hold the memorable reception at Nijo-jo Castle, a World Heritage Site by the donations from SAMCO Inc. and Chairman Osamu Tsuji. The Mayor of Kyoto, Daisaku Kadokawa, attended the reception, and after the sake barrel breaking ceremony, a toast was made with sake in accordance with Kyoto City regulations.

This special issue of Plasma Chemistry and Plasma Processing contains 12 manuscripts based on the invited contributions presented at ISPC 25. All papers submitted underwent the full refereeing procedure of the journal. The peer-reviewed articles are by plenary speakers Thierry Belmonte [1] and Toshiro Kaneko [2] and from invited speakers Yuki Inada [3], Julian Schulze [4], Olivier Guaitella [5, 6], Ahmad Hamdan [7], Richard Clergereaux [8], Maria L. Carreon [9], Volker Hessel [10], Cristiane Yumi Koga-ito [11], Lucia D. Pietanza [12] and their coauthors. This selection is representative of the general themes of the symposium, with contributions dealing with both nonthermal and thermal plasma science and technology by means of experimental and computational approaches. Complete Symposium proceedings are available online at https://www.ispc-conference.org/index.php/proceedings.

Finally, we wish to thank all who contributed to the organization of ISPC 25.