Francesco Scarcello received the PhD degree in Computer Science from the University of Calabria in 1997. He is a full professor of computer science (SSD ING-INF/05) at the University of Calabria. His research interests are computational complexity, graph and hypergraph theory, constraint satisfaction, logic programming, knowledge representation, non-monotonic reasoning, and database theory. He has extensively published in all these areas in leading conferences and journals.
In particular, in database theory he solved some open problems on the complexity of acyclic conjunctive queries (Journal of the ACM 48(3):431-498,2001), and on some techniques to identify tractable classes of queries. From these studies the idea of a new notion of degree of cyclicity for hypergraphs, called hypertree-width came out. It turned out that this notion is the best technique for identifying tractable classes of hard problems, in that it is able to single out the largest islands of tractability among all other methods previously known in the literature (Artif. Intell. 124(2): 243-282, 2000, J. Comput. Syst. Sci. 64(3): 579-627, 2002, J. Comput. Syst. Sci. 66(4): 775-808, 2003, J. Comput. Syst. Sci. 73(3): 475-506, 2007). He participated in a number of national and international projects dealing with database and knowledge representation systems. In particular, the notions and the algorithms proposed in his Phd thesis have been used for developing DLV, a widely used knowledge-base management system based on disjunctive logic programming (Inf. Comput. 135(2): 69-112, 1997, ACM Trans. Comput. Log. 7(3): 499-562, 2006). His work on the complexity of Nash equilibria in non-cooperative games received in 2008 the IJCAI-JAIR Best Paper Prize, which is awarded to an outstanding paper published in JAIR in the preceding five calendar years. His paper ``Hypertree Decompositions and Tractable Queries'' received in 2009 the PODS Alberto O. Mendelzon Test-of-Time Award, which is awarded every year to a paper or a small number of papers published in the PODS proceedings ten years prior that had the most impact in terms of research, methodology, or transfer to practice over the intervening decade.