This article contends that the problem of classroom order rests less in the roles and compositions of classrooms than in the multidimensional nature of their social situations. Classroom order arises from the dynamic relationship between distinct situational requirements: the coordination of interaction into institutionalized patterns (routine) and the validation of participants' identities (ritual). Utilizing a unique data set of more than 800,000 turns of talk from 601 high school classrooms, the authors develop metrics for measuring the longitudinal accomplishment of routine (interactional stability) and ritual (interactional concord) and present two sets of analyses. The first analyses identify the antecedents to stability and concord, and the second examine how stability and concord shape the experiences and attitudes of classroom participants. Results indicate that activities and discourse combine to fulfill the requirements of ritual and routine in different ways, often meeting one at the expense of the other, and that the accomplishment of stability and concord has positive returns to classroom experiences, but in different ways for teachers and students. (Contains 9 notes, 7 tables, and 3 figures.)