Despite their joint responsibility for creating, communicating, and delivering customer value, relationships between marketing and sales (M&S) functions are often suboptimal and fraught with conflict. Yet, the complex nature of M&S conflict, as well as conflict management techniques, have been insufficiently explored. We collect data from 252 M&S managers at large US firms to test a moderated mediation conceptual model. This study explores M&S latent conflict and manifest conflict and empirically tests the link between them. We also examine flexible conflict intervention (FCI) as a mitigating factor in a conditional relationship between task conflict and firm performance. We find that both competition for resources and relative functional identification positively predict M&S task conflict, while divergence of goals has no such effect. Moreover, FCI attenuates the harmful effects of task conflict on firm performance. This study benefits practitioners and researchers with new insights regarding conflict management solutions at the M&S interface.