In industrialized countries, maize cultivation is mainly associated with the use of hybrid varieties and input-intensive monocultures. Despite the homogeneity of European maize landscapes, alternative models of maize production based on landraces exist. Understanding the structures and values underlying these models is essential to enable the design of new strategies linking crop diversity, plant breeding, and food systems. This paper analyses the introduction of maize landraces by a farmers' association in Aquitaine (France) and two farmers' associations in Veneto (Italy), identifying what shapes and sustains different forms of landrace management. The Aquitaine group manages a broad panel of maize landraces collected from different regions of the world in a multi-site farm network. They have also developed new open-pollinated varieties, mostly for animal feed. In contrast, each of the Veneto groups has adopted only one maize landrace, within a cooperative system linking local maize and food practices. In both cases, the adoption and management of landraces are shaped by different productive priorities, but also by larger projects wherein new practices and values are created simultaneously. This is an ongoing process of developing new landraces as well as alternative forms of conservation, breeding and socialization among farmers.