The social and natural worlds provide heterogeneous resources that contribute both to instances of social identification and to life trajectories. One might claim or be assigned membership in various groups, which emerge at different spatial and temporal scales, and resources for social identification are often combined in novel ways to yield unexpected identities. To account for the trajectories of identification that any individual travels, analysts must determine which configurations of resources become relevant in a given case. Of the many resources that might be relevant to identifying an individual, event, or setting, a few generally become salient—somewhat like several musical notes coming together to constitute a chord. We illustrate this contingent process by describing one young Mexican migrant in the USA, sketching relevant aspects of family interactions, educational practices, local community characteristics, and national discourses. This girl, her family, and other actors combine heterogeneous resources in contingent ways as they navigate and establish an emerging trajectory of identification through which she becomes a ‘good reader’.