We are pleased to announce that the following speakers have accepted to give invited talks at Tableaux 2009:

**Patrick Blackburn**, INRIA Nancy, France

*Family Secrets*

**Peter Jeavons**, Oxford University Computing Laboratory, UK (Joint speaker with FTP)

*Introducing Constraints*

I will introduce the constraint satisfaction problem and show that it unifies a very wide variety of computational problems. I will then discuss the techniques that have been used to analyse the complexity of different forms of constraint satisfaction problem. I will focus on the algebraic approach, explaining the basic ideas and highlighting some of the recent results in this area.

**Pierre Wolper**, Université de Liege, Belgium

*On the Use of Automata for Deciding Linear Arithmetic*

This talk presents a survey of automata-based techniques for representing and manipulating linear arithmetic constraints. After introducing the basic concepts used in this approach, both representing integer constraints by finite-word automata and real constraints by infinite-word automata is discussed. Various results about the construction of automata from constraints and about the specific properties of automata representing arithmetic constraints are then presented. Finally, it is shown how this approach leads to simple and natural decision procedures that are in some ways related to tableaux.