Alfred Sloan ran GM from the 1920s to the '50s. During that time he led GM to become the world's largest corporation — in the '50s, GM held 46% of the US auto market and employed over 600,000 Americans. Sloan is also credited with inventing modern corporate structure. According to leadership guru Peter Drucker, the follow-up memo was one of Sloan's go-to tools. After any formal meeting — in which he simply announced the purpose, listened to what people had to say, and then left — Sloan would send a follow-up memo with a plan of action. Drucker's take: These memos made Sloan an outstandingly effective executive, Drucker argues, and you might say they were a key to GM's dominance of the 20th century.Back when he was a CEO, Ben Horowitz led Opsware to a $1.6 billion sale to HP in 2007.Two years later, he cofounded Andreessen Horowitz, a highly sought-after firm in venture capital. Horowitz, who spends much of his time mentoring young leaders, says that most important job for a CEO is to architect the way people communicate in a company. The one-to-one meeting is essential to that process, he says, as it's the best place for ideas and critiques to flow up from employees to management.Here's his take on how to run one: Musk has incredibly high standards. He has a reputation for firing people if they miss a deadline. So if you're meeting with him at Tesla or SpaceX, you have to be ready.In an April 2018 company-wide email obtained by Jalopnik, Musk had this to say about meetings:Sandberg brings a spiral-bound notebook with her to every meeting. In that notebook is a list of discussion points and action items. She crosses them off one by one, and once every item on a page is checked, she rips the page off and moves to the next, Fortune reports. If every item is done 10 minutes into an hour-long meeting, the meeting is over.Jobs led Apple to become one of the world's most valuable companies, creating consumer-friendly products with sleek designs. He ran meetings with a similar minimalism. He hated when they were too big, because too many minds in a room got in the way of simplicity. In one tale, Jobs was in a weekly meeting with Apple's ad agency and spied someone who didn't regularly attend. He asked who she was, listened to her reply, and politely told her to get out: I don't think we need you in this meeting, he said. Thanks.Jobs carried the same standard with himself: When US President Barack Obama asked him to a meeting of tech darlings, he declined. The guest list was too long.As we've reported before, Mayer gets to the bottom of any proposal brought her way.Product managers or designers who would sit down with the former Yahoo exec would have their strategies thoroughly vetted through a series of questions, like: How was that researched?What was the research methodology?How did you back that up?These questions are just one aspect of the many strategies Mayer used to shake up Yahoo.Page became CEO of Google in 2011, until Sundar Pichai took over in the role in 2015.He immediately sent out a company-wide email. The subject: how to run meetings effectively. One of his tips is to designate a decision-maker for every meeting. But even more importantly, Page made the point that you might not need a meeting at all. No decision should ever wait for a meeting, the email reads. If a meeting absolutely has to happen before a decision should be made, then the meeting should be scheduled immediately.Former Nike CEO Mark Parker would walk into meetings with a Moleskine notebook under his arm — full of his sketches of new products.In 2009, cyclist Lance Armstrong was in a business meeting with Parker, who spent the whole time doodling in his notebook. At the end of the meeting, Armstrong asked to see what he drew. He turns the pad over and shows me this perfect shoe, Armstrong recalls.The doodles help clarify the brainstorming process, Parker said, one that's a constant balance between what design wants and what business needs. I think about balance a lot, Parker said. Most of us are out of balance, and that's OK, but you need to keep your eye on the overall equilibrium to be successful.Stoppelman has a one-on-one meeting with each of his direct reports every week. Sometimes I feel like the company's psychiatrist, he shared on a Reddit AMA, but I do feel like listening to people and hearing about their problems (personal and professional) cleans out the cobwebs and keeps the organization humming.At any given meeting at Evernote, there will be someone there who doesn't belong. This is by design. The cloud note-taking startup has an internal program called officer training, in which employees get assigned to meetings that aren't in their specialty area to explore other parts of the company.They're there to absorb what we're talking about, Phil Libin says. They're not just spectators. They ask questions; they talk.Libin, who is Evernote's cofounder and former CEO, got the idea from talking with a friend who served on a nuclear submarine. To be an officer of such a sub, you had to know how to do everybody else's job. Those skills are repeatedly trained and taught, he says. And I remember thinking, 'That's really cool.'If you work at Amazon, you'd better be comfortable with conflict. Jeff Bezos is famous for hating social cohesion, that tendency people have for finding consensus for no other reason than it feels good. That distaste for agreeability is reinforced by Amazon's leadership principles, one of which reads: Huntley Ritter, the CEO of interactive advertising firm USeek, worked with Richard Branson at Virgin Group between 2011 and 2016. Speaking to Business Insider about his experiences with the British billionaire, Ritter explained that Branson never allowed sit-down group meetings.It's genius, he said. If you're standing, you're not going to chitchat for too long, and you're not going to have long, drawn-out conversations. He always just seemed to be more focused on, 'What are we trying to achieve? What's the result?'