This book constitutes the refereed proceedings of the First International Joint Conference on Automated Reasoning, IJCAR 2001, held in Siena, Italy, in June 2001. The 37 research papers and 19 system descriptions presented together with three invited contributions were carefully reviewed and selected from a total of 112 submissions. The book offers topical sections on description, modal, and temporal logics; saturation based theorem proving, applications, and data structures; logic programming and nonmonotonic reasoning; propositional satisfiability and quantified Boolean logic; logical frameworks, higher-order logic, and interactive theorem proving; equational theorem proving and term rewriting; tableau, sequent, and natural deduction calculi and proof theory; automata, specification, verification, and logics of programs; and nonclassical logics.

Invited Talks.- Program Termination Analysis by Size-Change Graphs (Abstract).- SET Cardholder Registration: The Secrecy Proofs.- SET Cardholder Registration: The Secrecy Proofs.- Algorithms, Datastructures, and other Issues in Efficient Automated Deduction.- Algorithms, Datastructures, and other Issues in Efficient Automated Deduction.- Description, Modal and temporal Logics.- The Description Logic ALCNH R + Extended with Concrete Domains: A Practically Motivated Approach.- NExpTime-Complete Description Logics with Concrete Domains.- Exploiting Pseudo Models for TBox and ABox Reasoning in Expressive Description Logics.- Exploiting Pseudo Models for TBox and ABox Reasoning in Expressive Description Logics.- The Hybrid ?-Calculus.- The Hybrid ?-Calculus.- The Inverse Method Implements the Automata Approach for Modal Satisfiability.- The Inverse Method Implements the Automata Approach for Modal Satisfiability.- Deduction-Based Decision Procedure for a Clausal Miniscoped Fragment of FTL.- Deduction-Based Decision Procedure for a Clausal Miniscoped Fragment of FTL.- Tableaux for Temporal Description Logic with Constant Domains.- Tableaux for Temporal Description Logic with Constant Domains.- Free-Variable Tableaux for Constant-Domain Quantified Modal Logics with Rigid and Non-rigid Designation.- Free-Variable Tableaux for Constant-Domain Quantified Modal Logics with Rigid and Non-rigid Designation.- Saturation Based Theorem Proving, Applications, and Data Structures.- Instructing Equational Set-Reasoning with Otter.- NP-Completeness of Refutability by Literal-Once Resolution.- Ordered Resolution vs. Connection Graph resolution.- A Model-Based Completeness Proof of Extended Narrowing and Resolution.- A Model-Based Completeness Proof of Extended Narrowing and Resolution.-A Resolution-Based Decision Procedure for the Two-Variable Fragment with Equality.- A Resolution-Based Decision Procedure for the Two-Variable Fragment with Equality.- Superposition and Chaining for Totally Ordered Divisible Abelian Groups.- Superposition and Chaining for Totally Ordered Divisible Abelian Groups.- Context Trees.- Context Trees.- On the Evaluation of Indexing Techniques for Theorem Proving.- On the Evaluation of Indexing Techniques for Theorem Proving.- Logic Programming and Nonmonotonic Reasoning.- Preferred Extensions of Argumentation Frameworks: Query, Answering, and Computation.- Bunched Logic Programming.- A Top-Down Procedure for Disjunctive Well-Founded Semantics.- A Second-Order Theorem Prover Applied to Circumscription.- NoMoRe: A System for Non-Monotonic Reasoning with Logic Programs under Answer Set Semantics.- NoMoRe: A System for Non-Monotonic Reasoning with Logic Programs under Answer Set Semantics.- Propositional Satisfiability and Quantified Boolean Logic.- Conditional Pure Literal Graphs.- Evaluating Search Heuristics and Optimization Techniques in Propositional Satisfiability.- QuBE: A System for Deciding Quantified Boolean Formulas Satisfiability.- System Abstract: E 0.61.- Vampire 1.1.- DCTP - A Disconnection Calculus Theorem Prover - System Abstract.- DCTP - A Disconnection Calculus Theorem Prover - System Abstract.- Logical Frameworks, Higher-Order Logic, Interactive Theorem Proving.- More On Implicit Syntax.- Termination and Reduction Checking for Higher-Order Logic Programs.- P.rex: An Interactive Proof Explainer.- JProver: Integrating Connection-Based Theorem Proving into Interactive Proof Assistants.- Semantic Guidance.- The eXtended Least Number Heuristic.- System Description: SCOTT-5.- Combination of Distributed Search and Multi-Search in Peers-mcd.d.- Lotrec: The Generic Tableau Prover for Modal and Description Logics.- The modprof Theorem Prover.- A New System and Methodology for Generating Random Modal Formulae.- Equational Theorem Proving and Term Rewriting.- Decidable Classes of Inductive Theorems.- Automated Incremental Termination Proofs for Hierarchically Defined Term Rewriting Systems.- Decidability and Complexity of Finitely Closable Linear Equational Theories.- A New Meta-Complexity Theorem for Bottom-Up Logic Programs.- Tableau, Sequent, Natural Deduction Calculi and Proof Theory.- Canonical Propositional Gentzen-Type Systems.- Incremental Closure of Free Variable Tableaux.- Deriving Modular Programs from Short Proofs.- A General Method for Using Schematizations in Automated Deduction.- Automata, Specification, Verification, and Logics of Programs.- Approximating Dependency Graphs Using Tree Automata Techniques.- On the Use of Weak Automata for Deciding Linear Arithmetic with Integer and Real Variables.- A Sequent Calculus for First-Order Dynamic Logic with Trace Modalities.- Flaw Detection in Formal Specifications.- CCE: Testing Ground Joinability.- System Description: RDL Rewrite and Decision Procedure Laboratory.- lolliCoP - A Linear Logic Implementation of a Lean Connection-Method Theorem Prover for First-Order Classical Logic.- Nonclassical Logics.- Muscadet 2.3: A Knowledge-Based Theorem Prover Based on Natural Deduction.- Hilberticus - A Tool Deciding an Elementary Sublanguage of Set Theory.- STRIP: Structural Sharing for Efficient Proof-Search.- RACER System Description.