Sooner or later, there is a tough message that sustainability champions need to deliver to harried business leaders—the business game they are playing can’t continue. It’s been fun, but if they keep playing the game the way they are, everyone will lose. The rules need to be updated— quickly. That contention is probably not the best conversation-opener with a senior business leader. But, at some point along the line, sustainability champions should be ready to gently help them see that their current model of doing business is not sustainable.