First-year programs and freshman learning communities (FLCs) have become an institutionalized feature of the higher-education landscape. Although a vast amount of literature asserts the positive consequences of these programs, less attention has been devoted to the unintended, and occasionally negative, consequences of FLCs. The author identifies the formation of the "peer cohort" as the central intended consequence of FLCs that also produces unintended student behaviors that may hinder student learning, student development, and faculty-student relations. A number of social-psychological theoretical principles are used to illustrate the peer cohort dynamics that emerge in FLCs.