His research interests lie in the area of Theoretical Computer Science. He works on algorithmic game theory, with emphasis on algorithmic aspects of congestion games and approximate mechanism design without money, and on the design and analysis of approximation and online algorithms, with emphasis on facility location problems. He has published more than 90 papers in major conferences and journals and has served on the program committees of some important conferences (ICALP-A, ESA-A, SWAT, EC, WWW, WINE, SAGT). His research has received more than 1800 citations (according to Google Scholar). His research results include asymptotically optimal algorithms for online and incremental facility location, a potential function for generalizations of congestion games with linear delays, and best possible approximate truthful mechanisms without money for facility location.