Introduction: Revising, Updating and Combining Knowledge; D. Dubois, H. Prade. Revision of Belief Sets and Belief Bases; S.O. Hansson. How Hard is it to Revise a Belief Base? B. Nebel. Conditionals and the Ramsey Test; S. Lindström, W. Rabinowicz. Logics for Belief Base Updating; A. Herzig. Reasoning about Merged Information; L. Cholvy. Numerical Representations of Uncertainty; P. Smets. Belief Change Rules in Ordinal and Numerical Uncertainty Theories; D. Dubois, S. Moral, H. Prade. Parallel Combination of Information Sources; J. Gebhardt, R. Kruse. Index.