In Conjunction with AAMAS 2010 Toronto , Canada , May 11 , 2010

Interaction protocols play a fundamental role in multi-agent systems. In this work, after analysing the trends that are emerging not only from research on multi-agent interaction protocols but also from neighbouring fields, like research on workflows and business processes, we propose a novel definition of commitment-based interaction protocols, that is characterized by the decoupling of the constitutive and the regulative specifications and that explicitly foresees a representation of the latter based on constraints among commitments. A clear distinction in the two representations has many advantages, that are explained in the paper, mainly residing in a greater openness of multi-agent systems, and an easier re-use of protocols and of action definitions. A language, named 2CL, for writing regulative specifications is also given.