Over the past 30 years, I've interviewed hundreds of executives, ranging from living legends to unknown entrepreneurs struggling with their initial startups, as well as dozens of sales and marketing gurus.

As an engineer and marketer, I've participated in the growth of a wildly productive organization and observed--firsthand and up close--as two huge companies disintegrated under the weight of their own collective stupidity.

For the past seven years, I've had daily conversations with scores of readers about surviving and thriving in the corporate world. Based on all of the above, this much I know is true:

1. You are a freelancer.

Regardless of whether you're the CEO of a huge company or a drone starting in the mailroom, you are a freelancer.

Even if you've got a salaried position with benefits, perks, paid vacations, and a fancy title, you are a freelancer.

Being a freelancer means that your value to your company, your peers, and your investors is only as good as your last win.

Being a freelancer means constantly developing new opportunities, defining new products, and planning three steps ahead.

There is one alternative to being a freelancer: being unemployed and unemployable.

2. You are your own boss.

CEOs get this, of course, but it's also true for everyone else. Since you're a freelancer, your manager--the person you "report" to--is more like a client or customer, which means you must constantly manage the relationship.

As a freelancer, you must be capable of managing not just upward and downward, but sideways as well. You must influence and convince your coworkers to help you achieve your goals, usually by helping them achieve theirs.

Most importantly, you must learn to manage yourself, controlling your thoughts, habits, and actions so that they serve your greater purpose.

3. You must learn to sell.

Selling is the soul of business. Companies that can't sell their products go bankrupt. Even nonprofits and government agencies depend entirely on somebody's ability to sell the usefulness of whatever service those organizations provide.

What's true for companies is absolutely true for you as a freelancer. Your ability to succeed will always be dependent upon your ability to sell yourself and your ideas.

Unless you want to be (or be seen to be) entirely irrelevant to everyone around you, you must not just learn to sell, but learn how to be good at it.

4. Clarity is power.

In the past, some businessfolk were like politicians and found it useful to blur issues with doubletalk, jargon, and biz-blab. The saying then was: "You can't pin Jell-O to the wall!"

Today, however, the business world is flooded with too much information. The endless challenge is now to simplify what's complex, without being simplistic.

Whoever can communicate clearly now commands vast power over the vast majority of people who are drowning in a sea of data.

5. People skills trump tech skills.

While it's generally useful to know how to use technology, your ability to create value (and to sell it to others) emerges from understanding other people, discovering what motivates them, and figuring out how to satisfy their individual needs.

6. Courage is real, security is not.

Forget job security because it doesn't exist. To fight--and win--against the inevitable changes and challenges that come into your life and industry takes courage.

Courage is not the same as being fearless. Only fools are fearless. Courage means taking risks to get what you want. Courage means facing the reality that if you stand up for what's right, you might lose your job or your company.

There is only one alternative: become a victim.

7. Your beliefs drive your results.

To be successful, you must differentiate between facts (reality) and beliefs (interpretations of what facts mean.) Your beliefs, not the facts, determine how well (or badly) you'll perform in any given situation.

For example, one person believes that a slow economy means, "It will be nearly impossible for me to sell this product." Another person might believe that "companies need my help now more than ever."

Which of the two is most likely to succeed?

8. Business is simple.

While every industry and every profession requires specific expertise, the business of business tends to be rather simple.

Unfortunately, the livelihood of hundreds of thousands of management consultants, industry analysts, and corporate trainers depends upon keeping things complex--because, after all, if business is simple, why hire those guys? Good question!

Beyond your own area of expertise, all you need to both survive and thrive in the business world is a handful of secrets and shortcuts, which is why I write this blog and why I wrote my most recent book.