Stéphane Saussier is a lecturer in Economics at the University of Paris-XI-Sceaux. He is a member of the Centre d’analyse des dynamiques industrielles et sociales (ADIS) and associate director of the Centre d’analyse théorique des organisations et des marchés (ATOM). He researches Organization Theory and contracts applied to various domains of activity. Anne Yvande-Billon is senior lecturer in Economics at the University Paris-I (Panthéon-Sorbonne). She is a member of the Centre d’analyse théorique des organisations et des marchés (ATOM) where she pursues research on Contract Economics.