Title of Symposium: Formalizing and Compiling Background Knowledge and Its Applications to Knowledge Representation and Question Answering Chairs names and affiliations: Chitta Baral, Arizona State University Organizing/program committee names and affiliations: Chitta Baral, Arizona State University Alfredo Gabaldon, NICTA Australia Michael Gelfond, Texas Tech University Joohyung Lee, Arizona State University Vladimir Lifschitz, University of Texas, Austin Steve Maiorano, ARDA Sheila McIlraith, University of Toronto Leora Morgenstern, IBM Table of Contents: Title: Macros, macro calls and use of ensembles in modular Answer Set Programming Authors: Saadat Anwar, Chitta Baral and Juraj Dzifcak Title: From WordNet to a Knowlege Base authors: Peter Clark, Phil Harrison, Tom Jenkins, John Thompson and Rick Wojcik Title: A Tool for Knowledge Base Integration and Querying Authors: Omar Elkhatib, Enrico Pontelli and Tran Cao Son Title: Building a repository of background knowledge using semantic skeletons Authors: Boris Galitsky Title: A Knowledge Module: Buying and Selling Authors: Joohyung Lee and Vladimir Lifschitz Title: Towards a Modular Action Description Language Authors: Vladimir Lifschitz and Wanwan Ren Title: An Introduction to the Syntax and Content of Cyc Authors: Cynthia Matuszek, John Cabral, Michael Witbrock and John DeOliveira Title: Combining Logical and probabilistic reasoning Authors: Michale Gelfond, Nelson Rushton and Weijun Zhu Title: Going places: notes on a modular development of knowledge about travel Authors: Michael Gelfond Short papers: Title: Hierarchical task libraries in (Con)Golog Authors: Alfredo Gabaldon Title: Development of a background knowledge-base about transportation and smuggling Authors: Richard Scherl Other presentations: Title :Speciyfing a Web Service Ontology in First-Order Logic (http://www.cs.toronto.edu/~sheila/papers/gru-mci-aaaiss06.html) Authors: Michael Grunigner and Sheila McIlraith Title: Approximate Objects are precise in some contexts Author: John McCarthy