This paper analyzes the participation of small farmers in the fresh fruit and vegetable supply systems of supermarkets in Mexico, using the case of small-scale guava farmers in the state of Michoacán. Several findings emerge. The most important determinants of access of these farmers to “more modern markets” channels are their territorial context and the way in which those territories interact with different markets, and their quasi-fixed capital assets. Farm size, education, and participation in organizations are not significant determinants (except for farm size in the Central Region). Policies and projects aimed at promoting the inclusion in modern markets of small-scale farmers such as those producing guava in Michoacán, must act on the territorial dimension of the problem of inclusion/exclusion, and not restrict themselves to actions aimed at improving the supply chains or the capacities of the households or their farms and organizations.