He is a full professor at the Faculty of Informatics[1] at the Vienna University of Technology (TU Wien), the head of the Algorithms and Complexity Group, and co-chair of the Vienna Center for Logic and Algorithms (VCLA) of TU Wien.
[2][3] Szeider received his doctorate in Mathematics from the University of Vienna in 2001 under the supervision of Professors Herbert Fleischner and Georg Gottlob while working as a mathematician at the Austrian Academy of Sciences.
[5][6] He is a co-chair of the Vienna Center for Logic and Algorithms, which he founded together with Helmut Veith in 2012.
[9][10] Szeider is best known for popularizing the notion of backdoor sets for SAT and other problems[11][12] and the introduction of dependency schemes for quantified boolean formulas.
He showed with coauthors that it is NP-hard to determine whether the clique-width of a given graph is smaller than a given bound.