this article on Microsoft’s website is a stop-you-in-your-clicks quote:
“My favorite part of this project? Leadership. This project, more than any other I’ve been a part of, had leadership. Not management, but leadership,” reflected Greg Bader, the program manager ... responsible for driving the execution and launch of the Microsoft.com home page project.
What an important distinction!
Addendum (4/17/2016): 17 Key Traits That Separate Managers From Leaders: