Gen. Stanley McChrystal is best known as the retired four-star U.S. Army general who served as commander of all U.S. and NATO forces in Afghanistan. He's credited with the death of Abu Musab al-Zarqawi, leader of Al-Qaeda in Iraq, and is known for speaking his mind—both when other military leaders were reluctant to challenge decisions, and in off-the-cuff political remarks to the press. This tendency toward over-communication may have been the beam that buckled, crumbling Gen. McChrystal's career. However, during his military tenure, bolstering in-force communications was arguably one of his greatest achievements. And in recent years, the skill has helped him build another career as an author, public speaker, and educator (that job may seem counterintuitive, McChrystal joked: "I could have never gotten into Yale; now I'm grading their papers"). McChystal spoke at the Inc. 500 Conference in Washington, D.C., about his leadership style, wide-ranging career, and what leaders in the business world can glean from military management styles. We've broken down the most intruiging lessons the general shared during his speech and an exclusive interview with's Christine Lagorio.

1. Let your guard down strategically.
When asked why he was photographed not wearing body armor, McChrystal said he generally didn't suit up into armor when on the streets in Afghanistan. "Why I didn't wear it is I would deal with Afghans daily. They wouldn't think, 'He's smart; he's in a helmet and armor.' They would think, 'He's not as brave as I am.'" It was not only a subtle tactic to bridge a culture gap, it was also a way to send his troops a message. "I was asking people to go out and risk their lives," he said. "You can't say one thing and then keep yourself in a hermetically sealed armored bubble."

2. Communication should be your top priority.
McChrystal is noted for having spent his commander's discretionary fund not on better guns, but on purchasing bandwidth so that all the nodes of his network could communicate with each other. He worked hard to create teams of teams in order to rival the tribal and social structure of the al-Qaeda organization. Maintaining this complicated structure required steady communications between parts of the network in far-flung locations. McChrystal explains his strategy:

What I believe is you need to establish processes, you need to establish correct forums—ways that you decide that you're going to communicate—and then you need to make that work. And part of that is the equivilant of a pump or a heart, and if the heart is not pumping information through the body just like it needs, then you have to do CPR. You have to force it to work. You have to force that information to flow both ways. Part of that is pumping information out, and part of it is creating an environment that pulls information in. You'll find that things like a cubicle wall or a walk across the street can be as wide as an ocean was 100 years ago.

Sometimes it's far more distance than a walk across the street that you're dealing with. "You can't get out there and touch people on the shoulder that much anymore—you have to use digital means," McChrystal says. That said, McChrystal, even at the height of conflict, says he made time to hand-write letters of praise or thanks. "I used to get thank-you notes for my thank-you notes," he says. "I'd find them framed in [the troops' bunk] areas."

3. Watch your communication etiquette.
Just communicating isn't enough; tone is extremely important to the message. McChrystal illustrates this by saying you should never respond to an e-mail with a two-letter reply. "What happens is someone writes a very good e-mail. They'll frame a problem and then they'll give background to it, and then they'll make a recommendation," McChrystal says. "They'll send it to their supervisor...and they get back, typically from a BlackBerry or smartphone, 'OK.'" What does that even mean? "I think it can mean that someone is so important that they can only send two letters. I think it means, for me, that I'll never write that person another e-mail. Because I don't know what that e-mail means." While a short e-mail can work between members of a married couple, or very close associates, dynamics at work involving hierarchy are too complex to disregard. "It can give the feel of fending someone off, that stops communications forever. I would never do it," McChrystal says.

4. Use Commander's Intent—especially in times of crisis.
The idea of clearly expressing your vision of an end result is know as Commander's Intent. And in a time of strain or uncertainty, McChrystal says it's crucial. "This sounds simple, but if you really go into most organizations and ask what winning is going to look like, [managers each] have different ideas," McChrystal says. "Once you define winning, you have to define strategy, and it will all roll in the same direction," he says.

5. Own your failings.
Following unflattering remarks about Vice President Joe Biden attributed to McChrystal and his aides in a Rolling Stone article, McChrystal offered his resignation to President Barack Obama. McChrystal's reaction today? "I'm absolutely comfortable with it; I have been since that day." When asked about issues in maintatining strong leadership in the face of bad press, McChrystal explained he believes the best thing a leader can do is communicate thoroughly with his or her team, and to the public. "When you do explain, you've got to tell them the truth," he says. "If you do an Enron and you say, 'All's well, I think you should buy stock,' and then you turn around and you're selling stock, then you've got a credibilty gap that communication isn't going to help."

6. Stay fit.
You're probably not hiking the mountains of Afghanistan from nine to five, but McChrystal believes that physical fitness should still be a priority for any leader. "It is a sign of, in my opinion, personal self-discipline. If you are willing to do the things that keep you healthy—and they don't have to be athletic, but to keep you healthy—I think that means that you've shown a level of self-discipline that I think translates sometimes into business," he says. And for him, it's not just physical. "I think it keeps me more alert. I know I'm a fairly intense person by nature. I know that if I work out in the morning, I'm a little easier to work with, a little easier for people deal with than I might be otherwise. So people in fact encourage me to go and work out in the mornings for that reason."