Invited Talks.- Concurrent Abstract State Machines and ?+? CAL Programs.- Molecules as Automata.- Service-Level Agreements for Service-Oriented Computing.- Contributed Papers.- Tiles for Reo.- C-semiring Frameworks for Minimum Spanning Tree Problems.- What Is a Multi-modeling Language?.- Generalized Theoroidal Institution Comorphisms.- Graph Transformation with Dependencies for the Specification of Interactive Systems.- Finitely Branching Labelled Transition Systems from Reaction Semantics for Process Calculi.- A Rewriting Logic Approach to Type Inference.- A Term-Graph Syntax for Algebras over Multisets.- Transformations of Conditional Rewrite Systems Revisited.- Towards a Module System for K.- Property Preserving Refinement for Csp-Casl.- Reconfiguring Distributed Reo Connectors.- A Rewrite Approach for Pattern Containment.- A Coalgebraic Characterization of Behaviours in the Linear Time – Branching Time Spectrum.- Heterogeneous Logical Environments for Distributed Specifications.- Term-Generic Logic.- Declarative Debugging of Rewriting Logic Specifications.- Translating a Dependently-Typed Logic to First-Order Logic.

This book constitutes the thoroughly refereed post-conference proceedings of the 19th International Workshop on Recent Trends in Algebraic Development Techniques, WADT 2008, held in Pisa, Italy, on June 13-16, 2008. The 18 revised full papers presented together with 3 invited talks were carefully reviewed and selected from 33 presentations at the workshop. The papers focus on the algebraic approaches to the specification and development of systems, and address topics such as formal methods for system development, specification languages and methods, systems and techniques for reasoning about specifications, specification development systems, methods and techniques for concurrent, distributed and mobile systems, and algebraic and co-algebraic foundations.