• 1 Laboratoire Bordelais de Recherche en Informatique
• 2 Laboratoire d'Informatique, Signaux, et Systèmes de Sophia Antipolis
• 3 École Supérieure en Sciences Informatiques

This paper presents a new systematic approach for the uniform random generation of combinatorial objects. The method is based on the notion of object grammars which give recursive descriptions of objects and generalize context-freegrammars. The application of particular valuations to these grammars leads to enumeration and random generation of objects according to non algebraic parameters.