RecruitingBehavioural interventionUsing EMA Data to Inform a Web-intervention for Couples Concerned About DrinkingAlcohol misuse is a prevalent and serious problem with significant harms to society, individuals, and their relationships. Romantic partners have a strong influence on their partner's behavior, uniquely positioning them as a motivator and supportive factor in changing their partner's alcohol use, but little evidence exists on the specific ways they can influence their partner. The impact this has on the quality of their relationship, communication, and overall well-being has yet to be explored. Thus, this study utilizes qualitative, quantitative, and ecological momentary assessment (EMA) data from both partners to develop a web-based intervention that applies communication-based personalized feedback to support the concerned partner (CP) in motivating their drinking partner (DP) to reduce drinking and other adverse relationship outcomes.