Drawing on emotion regulation theory, this study investigates if and how emotion suppression informs relationship viability within new venture teams (NVTs) when such teams face obstacles. In particular, we use a dyadic approach to examine the suppressor’s authenticity and team members’ perceptions of appropriateness as mediators in the link between emotion suppression and relationship viability. A round-robin study with 93 respondents nested in 37 NVTs, which generated 167 observations, provides empirical support for the theoretically derived model by showing that both authenticity and appropriateness fully mediate the relationship between emotion suppression and relationship viability. In particular, the findings show that the negative indirect effect of emotion suppression on relationship viability via authenticity is larger than the positive indirect effect via appropriateness. A follow-up study after two years indicates that relationship viability and emotion suppression significantly predict venture survival. Together, these findings make ample contributions to the literature and provide interesting opportunities for further research.