What makes a leader great? All entrepreneurs and CEOs face a similar challenge: Inspiring employees to work together. Management gurus, from Peter Drucker to Tony Hsieh, have offered insights about forming collaborative work environments, but few have attempted to apply a more scientific approach to finding the key ingredient for great leadership.

As One: Individual Action, Collective Power, released earlier this month by Portfolio/Penguin, offers eight models, or "archetypes," for successful leadership scenarios. Jim Quigley, CEO of Deloitte, and Mehrdad Baghai, founder of Alchemy Growth Partners, spent months analyzing case studies of successful companies, from Linux to Cirque du Soleil. Their research pointed them to archetypes of effective leadership, from "Landlord and Tenants" to "Architect and Builders." According to Baghai, the book gives readers a new "way of understanding the dynamic of leadership that previously defied words." Quigley and Baghai recently spoke with Inc.com's Eric Markowitz.

What was the inspiration behind As One?

JQ: I've been fascinated by leadership for a long period of time, and I've had the privilege to be in a leadership position throughout my career. I provided an event in Australia, and Mehrdad was in the room, and after the conversation we sat down and worked out our views of leadership on a whiteboard. We discovered that we view leadership in very similar ways, coming at them from slightly different perspectives. So I began the process of every time I was with a CEO or CFO, having a conversation with them about leadership, and what I discovered was, this is where executives live. People are fundamentally challenged by leadership and the advantages and opportunities it provides. That spawned the project. This message is timeless, and the way I like to describe it is that leadership needs a very simple idea in order to have it resonate and be something than can be easily absorbed. We found that as one was an effective way of distilling leadership down to two simple words.

MB: People tend to talk about leadership as though it's one set thing—"here's the three things you need to do." What we knew was that there was no robust way of thinking about this. What we wanted to do was come at this thing in a much more analytically rigorous way and ask, What are the different types of leader-follower behaviors that are effective, and when did they work?

Many companies benefit from a collaborative environment, but perhaps some don't. What determines if your employees are working well together?

MB: Imagine if you took the entire organization you're thinking about, whether it's a start-up with 20 people or a large organization with several hundred thousand people. Imagine if you could do an MRI of every one of their brains and see how each of these people think about how they're working with the others. What you want to do is add up all those MRIs and see if they're consistent or if people have really different views. What we're beginning to notice is that consistency is important—as long as there's reasonable consistency among the people in the organization, it seems to work well.

The book presents examples of leadership from people outside the traditional business community, such as Gandhi and Jerry Bruckheimer. Why?

JQ: When you think about that ambition to bring together diverse individuals and behave as one, I think we're thinking way too narrowly if we're just looking for the business examples. So in the research we looked at examples in science, the military, and historical examples, and it helped to inform our thinking. I think there's learning from the Mandela example, just like there's great learning from Gandhi. For example, the symbolism of Gandhi when he steps off the boat in the traditional Indian attire, even though he was trained as a British barrister. He didn't come off that boat in a business suit—people connected with him and were ready to follow him.

We often hear that a great leader needs to be charismatic. Is this always true, or are there times when a silent leader is better for an organization?

JQ: It depends on the model that you're using to drive and sustain your "as one" behavior. When you start at the top of our chart, the charismatic Steve Jobs is important in the model that we used to illustrate that and his ability to become the "Landlord." But if you move down to the other end of the spectrum and look at "Community Organizer and Volunteers," I'm not sure that we would describe Linus Torvalds (founder of Linux) as a charismatic leader. But with open-source software of Linux, you see hundreds of thousands of software engineers coming together around that community.

Doesn't the size of the organization make a difference? For example, Jim, you manage a company with 170,000 employees. That is far different from a three-person tech start-up.

JQ: What we believe we've created is the next practice. We're talking about collective leadership in the context of leadership behavior as opposed to leadership attributes. I believe that this thinking cascades very deep into the organization. For example, in Deloitte, this ambition cascades to my country leaders, to my line of business leaders, and importantly, I believe this ambition cascades all the way to a project partner leading a project for a client. If he can, with his team of 10, have that team work together as one, in pursuit of the ambition of delivering value to that client, that team is going to have an advantage over another team.

There are hundreds, if not thousands, of books on leadership. What does the current literature on management lack that you wanted to address?

MB: I kept running across books where people would take a characteristic and make it a prescription for all companies. For example, the reason fire ants can survive torrential downpours in the Amazon is because they come together and form a living raft. That kind of behavior is fantastic, and the lessons we can learn from that are fantastic, too, but what goes too far is when people say, this works great for ants, therefore at IBM we should use it. Well, only if you're facing a context that demands it. If, on the other hand, the context demands real creative innovation, then you should do "Producer and Creative Team." I think essentially what's happening is that people basically have a two-pixel view of the world. It's command-and-control versus collaborative-or-adaptive. And basically the theme in modern literature is that command-and-control: bad. Collaborative: good. But why is command-and-control bad? There are lots of examples where it works brilliantly. Let's not throw the baby out with the bath water. Surely there are more than two types of leadership.

Why eight archetypes? Why not 10 or 50?   

MB: Based on our cases, we managed to get to eight. We're convinced there's more. It's kind of like discovering your first species of animal—we've discovered eight of them, and part of what we're trying to do now is build a database of people identifying as many examples of collective leadership as they can, and run our analytics to discover the ninth and 10th. We see this as a new frontier—we're bringing a new granularity to this. People may not care that there's 15 archetypes in the end; maybe eight is enough. But what was clear was that two were too few.

How close should a leader be to the day-to-day aspects of a worker's life?

MB: Most entrepreneurs will work as "Architects" or builders. They will have a clear idea of what they want to build, but they will not micromanage people. An example is Shai Agassi when he started Better Place. He knew he was going to interact with car companies, with technology and software makers, with local government, so he brought in all the people with different skills. But he did not micromanage. The problem is that a number of people who join that community don't want all that freedom. They might want a little more specific instruction and guidance. It's a bit of a challenge.

How does a leader bring together a diverse group of people, especially in times of a merger or acquisition, like the recent AOL–Huffington Post acquisition. Aren't there bound to be culture clashes?

MB: When you think about work style, I imagine that Huffington Post and AOL have very different cultures. How do you get people to change their mental model of how they're supposed to work with others? Or do you decide that you put Huffington Post as a cocoon and let it maintain its own culture? Employees are going to make assumptions about the culture of this new place. We call it the Ukrainian Wedding Effect (don't ask me why). The idea is that if you've never been to a Ukrainian wedding, the first time you've been there, you're not going to know what to do. But as you observe and hang around, you're going to understand what you have to do. So the idea is that some cultures have that character about them. We try to give a language to companies to come to this, so it's easier for people to pick up the clues.