This paper proposes that intimacy is a process that emerges from a sequence of events in which behavior vulnerable to interpersonal punishment is reinforced by the response of another person. These intimate events result in an increase in the probability of behavior vulnerable to interpersonal punishment in the presence of the reinforcing partner. The process results in intimate partnership formation and reports of feeling intimate. In addition to positing an operant process integrating the various components of intimacy, the theory also posits that the punishment of interpersonally vulnerable behavior is an integral aspect of intimate partnership formation and that intimate partnerships can develop that reinforce behavior that may be destructive both to the individual and to others.