Anyway, as Drucker, Sealey and several other pundits have said, we're moving away from the old Prussian line-officer model (in which the general gives a command to the colonel, the colonel passes to the lieutenant colonel, the lieutenant colonel to the lieutenant, and so on right down to the private). Instead, we're following the 'orchestra model,' in which one leader gives direction to everyone, moving from the woodwinds to the brass as needed.

In addition, companies must move away from neat little job descriptions to a discussion of the work that a team or group of workers must accomplish. The content of work has taken "probably the most dramatic shift we will see in our lifetime," says Ms. O'Neal. "We have gone from a hierarchical organization to a symphony-orchestra model where work can rarely be done by an individual alone."