Although alcohol consumption has long been recognized as a risk factor in intimate partner violence, few studies have addressed whether acute alcohol consumption is a causal factor in episodes of relationship conflict or aggression. The proposed research will address the proximal relationship between alcohol consumption and relationship aggression among a community sample of young married and cohabiting couples. Two methods are proposed. First, an experimental study will examine the effects of alcohol, administered independently to male and female partners, on communication behaviors and verbal aggression within a conflict resolution paradigm. We hypothesize that alcohol consumption by either partner will increase behavioral negativity and verbal aggression. Second, a daily diary study will allow us to examine whether the likelihood of relationship conflict or aggression occurring on a given day is increased when either the man, the woman, or both have consumed alcohol earlier that day. In-depth, event-based interviews, conducted at the conclusion of the 8-week diary period, will provide insight into how alcohol may contribute to the initiation, escalation, and desistance of conflict. There are several unique aspects to the research. First, although the majority of research has focused on the role of men's drinking in their perpetration of aggression, women's drinking may contribute to relationship conflict and aggression as well. Thus, we will explicitly consider the role of women's drinking, independent of the drinking of their male partners, on relationship conflict and aggression both within the laboratory and in naturally-occurring conflict episodes. Second, the diary study promises to be the first to examine daily relationship between alcohol and episodes of relationship conflict in a non-clinical sample and is expected to address the relative importance of alcohol in naturally occurring relationship conflict. Third, recognizing that alcohol may not facilitate conflict or aggression for all couples, both studies will consider the role of potential moderating variables, including propensity toward aggression, behavioral self-control, and alcohol expectancies. Considering the proximal relationship between alcohol consumption and relationship conflict is expected to provide important insight into the causal mechanisms underlying the alcohol-intimate partner violence relationship.