Social psychologists have assumed that the sequence of symbolic acts between persons is a process; i.e., a sequence in which some stable contingency describes the relation between one act and the next. Yet there is virtually no research on interaction in natural settings in which it is shown that the sequence of symbolic acts is a process, or what kind of process it is. Data were collected from 1,622 police-civilian encounters by trained observers who rode with officers in a random shift sample. This sample was further limited to 95 encounters with two police officers and one civilian suspect, where 20 or more interactions took place. Analyses of these data support the hypothesis that police-civilian interaction is a process, a second-order process in which the actions of either participant at some time are contingent upon the combination of the most recent past actions of that and the other participant. The process is a Markov process with such important properties as its tendency to lead to an equilibrium distribution in which the distribution of different acts by each participant becomes relatively stable over time, predominated by mutually confirming responses, although there is continued change from state to state withing the context of that equilibrium. Officers exert and maintain control by determining the substantive focus of the interaction, seeking information, and creating identities and statuses. Confrontation eventuates from a civilian's refusal to accept the officer's definition of reality, not merely from disrespect. It is probable that much research on 'demeanor' and 'respect' has overemphasized those dimensions by failing to take into account the manifest symbolic dimensions of the interaction, a finding that has much significance for social psychology in general for the understanding of congnitive as well as interactional phenomena. Exemplary figures and 26 references are provided.