This volume contains the papers presented at the First International Sym- sium on Foundations of Information and Knowledge Systems" (FoIKS 2000), which was held in Burg, Germany from February 14th to 17th, 2000. FoIKSis intendedto beabiannualeventfocussingontheoreticalfoundations ofinformationandknowledgesystems.Itaims to takeupthe oldtraditionofthe conferenceseries MathematicalFundamentals ofDatabaseSystems" (MFDBS) which encouraged East-West collaboration in the e ld of database theory. F- mer MFDBS conferences were held in Dresden in 1987 (Springer LNCS 305, edited by Joachim Biskup, J anos Demetrovics, Jan Paredaens, and Bernhard Thalheim), in Visegr ad in 1989 (Springer LNCS 364, edited by J anos Demet- vics and Bernhard Thalheim), and in Rostock in 1991 (Springer LNCS 495, edited by Bernhard Thalheim, Jan os Demetrovics, and Hans-Detlef Gerhard). Another goal of the MFDBS conference series has always been to attract researchers working in mathematical e lds such as discrete mathematics, c- binatorics, logics, and nite model theory who are interested in applying their theories to researchon databaseand knowledgebase theory. To that end, FoIKS takes up the tradition of providing a forum for mathematical foundations in a speci c branch of computer science. A r st attempt to reestablish the MFDBS tradition was made in 1995 with a follow-up workshop Semantics in Datab- es" to ICDT (Springer LNCS 1358, edited by Bernhard Thalheim and Leonid Libkin).