This book constitutes the refereed proceedings of the International Workshop on Computational Methods in Systems Biology, CMSB 2003, held in Rovereto, Italy, in February 2003.The 11 revised full papers presented together with 2 invited papers, 7 position papers, and 11 abstracts were carefully reviewed and selected from 30 submissions. Among the topics addressed are modeling languages for systems biology, concurrency in biological systems, constraint programming, logical methods in systems biology, formal methods for the analysis of biomolecular systems, quantitative analysis of biomolecular systems, and simulation and modeling techniques for systems biology.

Invited Papers.- Cells as Computation.- Formal Modeling of C. elegans Development: A Scenario-Based Approach.- Regular Papers.- Causal ?-Calculus for Biochemical Modelling.- Graphs for Core Molecular Biology.- Contribution of Computational Tree Logic to Biological Regulatory Networks: Example from Pseudomonas Aeruginosa.- Modeling Cellular Behavior with Hybrid Automata: Bisimulation and Collapsing.- Multiscale Modeling of Alternative Splicing Regulation.- A Method for Estimating Metabolic Fluxes from Incomplete Isotopomer Information.- Dynamic Bayesian Network and Nonparametric Regression for Nonlinear Modeling of Gene Networks from Time Series Gene Expression Data.- Discrete Event Simulation for a Better Understanding of Metabolite Channeling - A System Theoretic Approach.- Mathematical Modeling of the Influence of RKIP on the ERK Signaling Pathway.- A Method to Identify Essential Enzymes in the Metabolism: Application to Escherichia Coli.- Symbolic Model Checking of Biochemical Networks.- Presentation Abstracts.- Coupled Oscillator Models for a Set of Communicating Cells.- Representing and Simulating Protein Functional Domains in Signal Transduction Using Maude.- A Core Modeling Language for the Working Molecular Biologist (Abstract).- Integrating Simulation Packages via Systems Biology Mark-Up Language.- Recreating Biopathway Databases towards Simulation.- How to Synthesize an Optimized Genetic ?-Switching System? A System-Theoretic Approach Based on SQP.- Simulation Sudy of the TNF? Mediated NF-?B Signaling Pathway.- Detection and Analysis of Unexpected State Components in Biological Systems.- Model Validation of Biological Pathways Using Petri Nets - Demonstrated for Apoptosis.- An Overview of Data Models for the Analysis of Biochemical Pathways.- DiscreteEvent Systems and Client-Server Model for Signaling Mechanisms.- Position Papers.- Enhanced Operational Semantics in Systems Biology.- Issues in Computational Methods for Functional Genomics and Systems Biology.- Integrating Biological Process Modelling with Gene Expression Data and Ontologies for Functional Genomics (Position Paper).- Computer Simulation of Protocells.- How to Solve Semantic Puzzles of Systems Biology.- Evolution as Design Engineer.- Inference, Modeling and Simulation of Gene Networks.