Combining theories of social motives, goal interdependence, and conflict management, this study theorized a model in which interdepartmental goal interdependence affects conflict outcomes between different departments through open-minded discussion dynamics adopted by employees from different departments in the organization. This study also proposes that social motives moderate the link between inter-departmental goal interdependence and open-minded discussion. A sample of 133 employees from different business organizations in China were interviewed to recall a critical incident when they had a conflict with their coworker from different departments. SEM results and other analysis results support the hypotheses that cooperative interdepartmental goal interdependence and competitive goal interdependence are antecedents to employees engaging in open-minded discussion in the context of interdepartmental collaboration, and that open-minded discussion in turn influences conflict outcomes, i.e. task accomplishment, relationship strengthening, and future collaboration. Results further suggest that employee’s pro-social motive moderates the relationship between competitive goal interdependence and open-minded discussion, and that proself motive moderates the relationship between cooperative goal interdependence and open-minded discussion. Findings also suggest that practitioners promote effective interdepartmental collaboration by strengthening their prosocial motive when perceiving competitive goal and proself motive when perceiving cooperative goal, setting cooperative interdepartmental goal interdependence, and handling conflict through open-minded discussion. The study contributes to conflict management literature as well as the goal interdependence theory in the organizational behavior literatures.