Thisvolumecontainsthe66contributedpapersandabstractsofthethreeinvited lecturespresentedatthe11thAnnualEuropeanSymposiumonAlgorithms(ESA 2003), held in Budapest, September 16-19, 2003. The papers in each section of the proceedings are arranged alphabetically. The three distinguished invited ' speakers were Bernard Chazelle, Roberto Tamassia, and Eva Tardos. Forthesecondtime,ESAhadtwotracks,withseparateprogramcommittees, which dealt respectively with: The design and mathematical analysis of algorithms (the "Design and Analysis" track); Real-world applications, engineering, and experimental analysis of al- rithms (the "Engineering and Applications" track). Previous ESAs were held at Bad Honnef, Germany (1993); Utrecht, The Neth- lands (1994); Corfu, Greece (1995); Barcelona, Spain (1996); Graz, Austria (1997); Venice, Italy (1998); Prague, Czech Republic (1999); Saarbruc .. ken, Ger- ? many (2000); Arhus, Denmark (2001), and Rome, Italy (2002). The predecessor to the Engineering and Applications track of ESA was the annual Workshop on Algorithm Engineering (WAE). Previous WAEs were held in Venice, Italy (1997), Saarbruc .. ken, Germany (1998), London, UK (1999), Saarbruc .. ken, Ger- ? many (2000), Arhus, Denmark (2001), and Rome, Italy (2002) . The proceedings of the previous ESAs were published as Springer-Verlag's LNCS volumes 726, 855, 979, 1284, 1461, 1643, 1879, 2161, and 2461. The p- ceedings of the WAEs from 1999 onwards were published as Springer-Verlag's LNCS volumes 1668, 1982, and 2141.

This book constitutes the strictly refereed post-conference proceedings of the 5th International Symposium on Graph Drawing, GD'97, held in Rome, Italy, in September 1997. The 33 revised full papers and 10 systems demonstrations presented were selected from 80 submissions. The topics covered include planarity, crossing theory, three dimensional representations, orthogonal representations, clustering and labeling problems, packing problems, general methodologies, and systems and applications.

This book constitutes the refereed proceedings of the Third Italian Conference on Algorithms and Complexity, CIAC'97, held in Rome, Italy in March 1997.
The 25 revised full papers included in the volume were carefully selected from a total of 74 submissions; also included is an invited paper and an invited abstract. All in all, the papers present an interesting snapshot of current research activities and recent results in theory and applications of sequential, distributed, and parallel algorithms, data structures, and computational complexity.