I've been an entrepreneur for a long time. Besides being fortunate to find success with several of the companies I founded, I've also had the privilege to work with and know some of the most extraordinary (and extraordinarily successful) business people in the world.

What are they like? What sets those that build billion-dollar businesses apart from the average entrepreneur? In my experience, those that achieve truly spectacular success usually share a few common characteristics about how they approach their work and their lives. Here are a few of these essential differences:

1. Forget passion. You need obsession.

Maybe you've heard that success takes passion. I don't agree. Being successful in life is not about passion; it's about being obsessed. If you can sleep well, that's not the sort of obsession I'm talking about. If you have to get up on stage and tell someone 'I'm really passionate about X', it's too late. People have to tell YOU that you're obsessed about something. You shouldn't be telling them.

2. Details aren't beneath you.

To get from a crazy idea to a billion dollars, not only do you have to be obsessed but you also have to believe that no detail is too small to deserve your attention, because more often than not, especially in the early-stages of building a business, companies fail because you missed some small detail. They rarely fail because you missed the big picture.

3. Get to know people who are nothing like you.

We often learn the most from those who are least like us, be that an expert in a very different field from your own or even a homeless person. Billionaires don't only seek out and talk with those that resemble them; they're open to building relationships with people from all walks of life.

This is true when it comes to everyday life, attending a cocktail party, and even finding a co-founder. You ideal co-founder is completely unlike you and fills in the skills you lack. So, for example, part of the way you can take care of all the essential details I mentioned in point two, if you're not by nature a detail-orientated person, is to work with someone who is complementary to you. If your job is to go out and blaze the way through uncharted territory, this is the person who comes behind you and cleans up the mess.

4. There are two paths to a billion.

To become a billionaire, at least conceptually, is really, really easy. You need to be the type of dreamer who solves a $10 billion problem. It should be obvious, but it's worth repeating--you can't become a billionaire by solving a $10 million problem. How do you find a problem on this massive scale? There are two ways to think big enough (so big that if people call you crazy, you know you're on the right track).

The first is to solve a problem that impacts a billion people. If you can solve a problem like that, even if it's a problem with a modestly priced solution, you'll be on your way to being a billionaire. The alternative is to solve a problem that is so painful--so big--for a small group of people, that they're willing to pay a large amount to fix it. For example, a cure for certain types of cancer wouldn't impact billions of people, but the people it does impact would be willing to pay almost any price for it.

5. The world runs on friendship and trust.

Most people have heard the old saying 'it's not what you know; it's who you know.' But I think this is only a partial truth. In business and in life, knowing people isn't enough--who genuinely likes and trusts you is the important thing.

A better saying to remember is, 'people do business with people; companies don't do business with companies.' When you do a business deal, it should rarely be about you selling the product or service. It's about making the other party believe that you are a person they can trust and who's going to give their life to make sure this thing works. If the other person likes and trusts you, then objections and complications suddenly become easy to overcome, and it's amazing what you can accomplish together.

6. When it comes to relationships, quality beats quantity

How do you make the sort of warm, trusting connections I talked about in the last point? Some people think that the more business cards they give out, the more hands they shake, the better. I have a different view. Any time you make more than couple of friends at an event, I think that you actually made no friends. Building a small number of deep, meaningful connections is far more important than filling up your address book with casual acquaintances.

To nurture the sort of relationships that will truly help propel you towards accomplishing great things, you need to forget transactional networking, and focus on having in-depth conversations with fewer people about subjects you really care about. Taking off the mask and talking genuinely about your life and family with someone can be much more valuable than just talking up your business!

7. Humility is the surest sign of success.

In life we all struggle and strive to make progress. When will you know you've reached success? A billion dollars is a good sign, but there's a better one--humility. You know you've reached true success the day you become truly humble. That's the day you stop needing to prove to the world--and yourself--that you've accomplished something meaningful. If you have even one iota of arrogance left, you still have a ways to go. Focus on living a life of significance beyond just being financially successful.