While extant literature assumes an inverted U-shaped relationship between tie-strength and new knowledge acquisition, our study suggests a positive, curvilinear relationship. Our multiple case study shows that firms use specific relational capabilities—which we define “bridging capabilities”—to acquire new knowledge. These bridging capabilities mitigate the risk of overembeddedness in strong ties through increasing multiplexity, that is, through establishing and leveraging multiple relations within a single tie. Our findings suggest that small firms should invest more in the exploration of strong ties instead of increasing their weak tie network. Doing so helps them to reduce alliance complexity, thereby increasing alliance management efficiency and alliance ambidexterity.