Résumé
The agroecological transition of the French agrifood sector is an important challenge for sustainability. This sector is distinguished from others by specific features, including its structuring into 'vertical' value chains. These specificities need to be examined carefully, as they condition the way in which innovation niches can emerge and transform the sociotechnical regime. In this article, we study a variety of agrifood value chain initiatives in France engaged in sustainable practices that can be related to certain dimensions of agroecology. These initiatives are analysed through the prism of the "innovation functions" of Hekkert et al. (2007) to deepen the nurturing step of such value chain innovation niches. We added two functions: a function of governance and coordination and a function of network development. As outcomes, we highlight 1) the relative importance of the different innovation functions during the nurturing phase; and 2) the singularities of the agrifood sector in general and of agrifood value chain initiatives in particular, notably i) the role played by dominant regime actors, ii) the importance of market differentiation, iii) the importance of practices objectivation through certification, iv) the problem of consumer preferences uncertainty; and v) the strategies of inter-value chain connexions, which are key for the transition.