This paper takes a closer look at innovation systems, including the various actors involved, their interrelationships, and governance mechanisms. Innovation systems operate at different levels, in terms of structure, functioning, and performance at the national level, and from two different angles: as a macrostructure that involves different functions and key organizations working on these functions, and as the composite of different innovation networks comprising individuals and local and national organizations.

How do the innovation platforms and facilitated networks currently deployed in the Global South help trigger dynamics of collaborative innovation that can be useful for the agroecological transition? What are the difficulties encountered and how can they be overcome? This chapter throws lights on these questions. The first part justifies the interest in studying the ecologisation of agriculture through the prism of collaborative innovation and of its paradoxes.