This volume contains the articles presented at the 6th International Symposium on Foundationsof
Informationand KnowledgeSystems (FoIKS 2010)which was held in So?a Bulgaria during February 15
19 2010. The FoIKS symposia provide a biennial forum for presenting and discussing
theoreticalandappliedresearchoninformationandknowledgesystems.Thegoal is to bring together
researchers with an interest in this subject share research experiences promote collaboration
and identify new issues and directions for future research. FoIKS 2010 solicited original
contributions dealing with any foundational aspects of information and knowledge systems. This
included submissions that apply ideas theories or methods from speci?c disciplines to
information and knowledge systems. Examples of such disciplines are discrete mathematics logic
and algebra model theory information theory complexity theory algorithmics and computation
statistics and optimization. Previous FoIKS symposia were held in Pisa (Italy) in 2008
Budapest (Hungary) in 2006 Vienna (Austria) in 2004 Schloss Salzau near Kiel (Germany) in
2002 and Burg Spreewaldnear Berlin (Germany) in 2000.FoIKS took up the tradition of the
conference series Mathematical Fundamentals of Database Systems (MFDBS) which initiated East
West collaboration in the ?eld of database theory. Former MFDBS conferences were held in
Rostock (Germany) in 1991 Visegrad (Hungary) in 1989 and Dresden (Germany) in 1987. The FoIKS
symposia are a forum for intense discussions. Speakers are given su?cient time to present their
ideas and results within the larger context of their research. Furthermore participants are
asked in advance to prepare a ?rst response to a contribution of another author.
