We are happy to announce the contents of ++ Volume 99 of the Information Systems Journal ++ Ishaq Zouaghi, Amin Mesmoudi, Jorge Galicia, Ladjel Bellatreche, Taoufik Aguili GoFast: Graph-based optimization for efficient and scalable query evaluation Information Systems, Volume 99, 2021, 101738, ISSN 0306-4379 https://doi.org/10.1016/j.is.2021.101738 Vangelis Sarlis, Vasilis Chatziilias, Christos Tjortjis, Dimitris Mandalidis A Data Science approach analysing the Impact of Injuries on Basketball Player and Team Performance Information Systems, Volume 99, 2021, 101750, ISSN 0306-4379 https://doi.org/10.1016/j.is.2021.101750 Giulio Ermanno Pibiri, Shunsuke Kanda Rank/select queries over mutable bitmaps Information Systems, Volume 99, 2021, 101756, ISSN 0306-4379 https://doi.org/10.1016/j.is.2021.101756 Alvaro Valencia-Parra, Angel Jesus Varela-Vaca, Maria Teresa Gomez-Lopez, Josep Carmona, Robin Bergenthum Empowering conformance checking using Big Data through horizontal decomposition Information Systems, Volume 99, 2021, 101731, ISSN 0306-4379 https://doi.org/10.1016/j.is.2021.101731 Chin-Hui Lai, Chia-Yu Hsu Rating prediction based on combination of review mining and user preference analysis Information Systems, Volume 99, 2021, 101742, ISSN 0306-4379 https://doi.org/10.1016/j.is.2021.101742 Reem Alharthi, Areej Alhothali, Kawthar Moria A real-time deep-learning approach for filtering Arabic low-quality content and accounts on Twitter Information Systems, Volume 99, 2021, 101740, ISSN 0306-4379 https://doi.org/10.1016/j.is.2021.101740 Editors-in-Chief Dennis Shasha, Gottfried Vossen, Matthias Weidlich