Peer review is an essential part in the publication process, ensuring that Challenges maintains high quality standards for its published papers. In 2017, a total of 28 papers were published in the journal. Thanks to the cooperation of our reviewers, the median time to first decision was 22 days and the median time to publication was 44 days. The editors would like to express their sincere gratitude to the following reviewers for their time and dedication in 2017:
| Aslam, Muhammad | Haro, Marta | Park, Jonghyun |
| Barzilov, Alexander | Hekkenberg, Robert | Pisciella, Paolo |
| Bishop, Laura | Hrad, Jaromir | Pitt, Joseph C. |
| Bishop, Laura | Inamura, Kentaro | Pouke, Matti |
| Boero, Ferdinando | Ioja, Cristian | Price, Dan |
| Bolotov, Leonid | Ishihara, Keiichi N. | Reynders, Glenn |
| Boulais, Anastasia | Ivanov, Stanislav | Ryusuke, NAKAMURA |
| Boumediene, Haddad | Jaksic, Vesna | Salo, Jessica |
| Boyer, Severine | Jenkin, Thomas | Santoni-Rugiu, Eric |
| Butler, Colin | Johansen, Guro Gravem | Satani, Nikunj |
| Capova, Klara Anna | Johansen, Guro Gravem | Savitski, Dzmitry |
| Capova, Klara Anna | Kazemi, Hamidreza | Sekhar, Praveen Kumar |
| Chang, Der-Wen | Kintzios, Spyridon | Serrano, Fernando |
| Chen, Yu-Chih | Kluiving, Sjoerd | Shiao, Yaojung |
| Clark, Charles M. | Krysinska, Karolina | Smith, Kelly |
| Crouch, Alan | Kumar, Suhas | Sun, Xiangcheng |
| Cui, Borui | Labeodan, Timilehin | Suñer Soler, Maria Rosa |
| Dill-Shackleford, Karen | Lee, Howard | Szekely, Gyorgy |
| Dzyuba, Sergei | Magalas, Leszek B. | Takeya, Satoshi |
| Eghbal, Ashkan | Marzano, Adelaide | Teprovich, Joseph |
| Erbacher, Terri A. | Masanotti, Giuseppe | Tong, Jingjing |
| Eriksson, Charli | Mathews, Anne E. | Trammell, Scott A. |
| Espejel, Ileana | McLaughlin, Hugh | Tucker, John |
| Faraone Mennella, Maria Rosaria | Mikheenko, Pavlo | Tzannatos, Ernestos S. |
| Filarowski, Aleksander | Milanese, Chiara | Veenhuizen, Bram |
| Gassman, Natalie R. | Nakano, Katsuyuki | Wähälä, Kristiina |
| Geißler, Gesa | Nusselder, Sanne | Watkins, Clinton |
| Giglia, Elena | Okuda, Nagako | Wegienka, Ganesa |
| Green, Brian | Omata, Kenji | Weitz, Keith |
| Hakonen, Aron | Oztanriseven, Furkan | Yung, Winco K.C. |
| Haneczok, Grzegorz | Papadamou, Stefanos |
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