It’s long been recognized that cross-functional collaboration is essential. Still, stubborn silos that bog down execution, hamper innovation, and slow decision-making are still a common and persistent challenge. In their work with company leaders, the authors have found that, without leaders working together at the top, silos and dysfunction are inevitable. The onus is therefore on senior leaders to knock down these silos — moving beyond their ability to lead their own teams to also prioritize leading across the organization. The authors discuss what sets successful cross-functional leaders apart.