What really makes people happy? It's a question I'm sure you've pondered and one that's always fascinated me. Everything we do -- our relationships, career, shopping, service work -- is aimed at making us happy. Yet I'm sure you've noticed at times, despite all you do to find happiness, you're left feeling that something vital is still missing. Or worse, if any of these things do make you happy, you find you're scared to lose them. Is there a way to cut to the chase -- and experience true and lasting happiness that isn't Dependant on external circumstances? In my new book, Happy for No Reason: 7 Steps to Being Happy from the Inside Out, I answer this very question.

After years studying happiness -- interviewing scores of experts and unconditionally happy people, as well as delving into the research from the burgeoning field of Positive Psychology -- I sat down one day to review my findings. Suddenly I had a simple, but profound "a-ha": there's a continuum of happiness:

Unhappy: We all know what this means: anxiety, fatigue, feeling blue or low--your "garden-variety" unhappiness. This isn't the same as clinical depression, which dramatically interferes with your ability to live a normal life, and for which professional help is absolutely necessary.

Happy for Bad Reason: When people are unhappy, they often try to make themselves feel better by indulging in addictions or behaviors that may feel good in the moment but are ultimately detrimental: drugs, alcohol, excessive sex, "retail therapy," compulsive gambling, over-eating and too much television-watching, to name a few. This kind of "happiness" is hardly happiness at all.

It is only a temporary way to numb or escape our unhappiness through fleeting experiences of pleasure.

Happy for Good Reason: This is what people usually mean by happiness: having good relationships, success in our careers, financial security, or using our talents and strengths well. It's the pleasure we derive from having the healthy things in our lives that we want.

Don't get me wrong. I'm all for this kind of happiness! It's just that being Happy for Good Reason depends on the external conditions of our lives -- if these conditions change or are lost, our happiness usually goes too.

That's when I realized that there is one more level on the happiness continuum -- Happy for No Reason.

Happy for No Reason: This is true happiness -- a neurophysiological state of peace and well-being that isn't dependent on external circumstances.

Happy for No Reason doesn't mean grinning like a fool 24/7 or experiencing a superficial high. Happy for No Reason isn't an emotion. In fact, when you are Happy for No Reason, you can have any emotion -- including sadness, fear, anger or hurt -- but you still experience that underlying state of peace and well-being.

Most of us focus on being Happy for Good Reason, stringing together as many happy experiences as we can, like beads in a necklace, to create a happy life. We have to spend a lot of time and energy trying to find just the right beads so we can have a "happy necklace."

Being Happy for No Reason, in our necklace analogy, is like having a happy string. No matter what beads we put on our necklace -- good, bad or indifferent -- our inner experience, which is the string that runs through them all, is happy, creating a happy life.

So it turns out, you can be Happy for No Reason. In fact, it's the happiness we've all been looking for. When you're Happy for No Reason, it's not that your life always looks perfect -- it's just that however it looks, you'll still be happy.

(Excerpted from the New York Times bestseller, Happy from No Reason: 7 Steps to Being Happy from the Inside Out, Free Press, January 2008, and reprinted with permission of the author, Marci Shimoff).