This Festschrift volume has been published to celebrate the lifelong scientific achievements of Farhad Arbab on the occasion of his retirement from the Centre of Mathematics and Computer Science (CWI). Over the years Farhad Arbab has sucessfully been engaged in scientific explorations in various directions: Software Composition, Service Oriented Computing, Component-based Software, Concurrency Theory, Coordination Models and Languages, Parallel and Distributed Computing, Visual Programming Environments, Constraints, Logic and Object-Oriented Programming. Farhad Arbab has shaped the field of Coordination Models and Languages. His insight that it is all about exeogeneous coordination gave rise to the striking elegance and beauty of Reo: an exogenous coordination model based on a formal calculus of channel composition. Reo has been extremely successful and is having a great impact in many of the areas mentioned above. The present volume collects a number of papers by several of Farhad's close collaborators over the years.

This Festschrift volume contains papers presented at a conference, Prakash Fest, held in honor of Prakash Panangaden, in Oxford, UK, in May 2014, to celebrate his 60th birthday. Prakash Panangaden has worked on a large variety of topics including probabilistic and concurrent computation, logics and duality and quantum information and computation. Despite the enormous breadth of his research, he has made significant and deep contributions. For example, he introducedlogic and a real-valued interpretation of the logic to capture equivalence of probabilistic processes quantitatively. The 25 papers included in this volume were carefully reviewed. They cover a large variety of topics in theoretical computer science."

This book constitutes the refereed proceedings of the First International Conference on Algebra and Coalgebra in Computer Science, CALCO 2005, held in Swansea, UK in September 2005. The biennial conference was created by joining the International Workshop on Coalgebraic Methods in Computer Science (CMCS) and the Workshop on Algebraic Development Techniques (WADT). It addresses two basic areas of application for algebras and coalgebras a" as mathematical objects as well as their application in computer science.

The 25 revised full papers presented together with 3 invited papers were carefully reviewed and selected from 62 submissions. The papers deal with the following subjects: automata and languages; categorical semantics; hybrid, probabilistic, and timed systems; inductive and coinductive methods; modal logics; relational systems and term rewriting; abstract data types; algebraic and coalgebraic specification; calculi and models of concurrent, distributed, mobile, and context-aware computing; formal testing and quality assurance; general systems theory and computational models (chemical, biological, etc); generative programming and model-driven development; models, correctness and (re)configuration of hardware/middleware/architectures; re-engineering techniques (program transformation); semantics of conceptual modelling methods and techniques; semantics of programming languages; validation and verification.

Coinduction is a method for specifying and reasoning about infinite data types and automata with infinite behaviour. In recent years, it has come to play an ever more important role in the theory of computing. It is studied in many disciplines, including process theory and concurrency, modal logic and automata theory. Typically, coinductive proofs demonstrate the equivalence of two objects by constructing a suitable bisimulation relation between them. This collection of surveys is aimed at both researchers and Master's students in computer science and mathematics and deals with various aspects of bisimulation and coinduction, with an emphasis on process theory. Seven chapters cover the following topics: history, algebra and coalgebra, algorithmics, logic, higher-order languages, enhancements of the bisimulation proof method, and probabilities. Exercises are also included to help the reader master new material.