Organizations are often run according to "the superchicken model," where the value is placed on star employees who outperform others. And yet, this isn't what drives the most high-achieving teams. Business leader Margaret Heffernan observes that it is social cohesion — built every coffee break, every time one team member asks another for help — that leads over time to great results. It's a radical rethink of what drives us to do our best work, and what it means to be a leader.