An important thesis discussed in the literature on shared agency is that group identification motivates pre-school children to act together. This paper aims at further illuminating this thesis by clarifying what triggers the process of group identification in young children. It is argued that joint attention, among other functions in supporting joint actions, can reveal to the co-attenders that they share some preferences. Since sharing preferences has been established by the literature to be a reliable motivation of group identification and (...) since joint attention has an early emergence in development, one can consider joint attention to be a putative trigger of group identification in pre-school children. If this is on the right track, group identification, joint attention, and preferences identify a cluster of minimal pre-conditions for joint actions. (shrink)