Roy Spence had two choices when he launched his advertising agency many years ago: He could build something he thought would make him a lot of money, or he could build something that would enrich his life. He chose the latter--eventually, economic success followed.

Every time Im around someone whos in the business of improving peoples lives verses making money, Im enriched and I say I want to be more like them, Spence says.

When times are good, Spence says, people can make money with average products. But under trying economic conditions, when wallets are shut, entrepreneurs must show that their businesses have value. Today, if you cant prove to your customers that your product or service improves their life, they dont have time for you, Spence says.

In Spences recently released book, Its Not What You Sell, Its What You Stand For, he guides leaders through their own journies of understanding how their companies make a difference and how to harness that purpose for greater success.

Spence recently spoke with Entrepreneur.com about his new book, how he found his own purpose and why entrepreneurs are the lifeline of our economy.

How did you find your purpose?
The key on my road to purpose: Realizing that people who are in business to make a positive difference in the world are the people I want to be around. At some point when you start a business, you have this entrepreneurial spirit of creating something that was not there before.

I have found if your business purpose goes beyond just making money, you will actually make more money--not all the time, not everyday, but at least youre in the business of making a difference so you have a purpose.

My purpose in life is to inspire and help people find their purpose--thats what I do.

In this economy, why is it important for entrepreneurs to find their purpose?
I think its more important than ever before to know your purpose and to be able to articulate it, put it in writing and then live it. Some people say, I dont have time for purpose now, I need to go make a sale. Let me tell you something, you can be out there trying to make a sale, but unless your customer believes you are in the business to help them, if your products and services are just commodities, youre not going to make it, because people arent going to spend money right now on things that arent going to make a difference.

If youre not necessary in peoples life, theyre not going to care--nice is gone. Purpose is necessary.

How should entrepreneurs go about finding their purpose?
A friend of mine said recently, "Once youve realized that youve dug yourself in a hole, the first thing you have to do is stop digging." Take a deep breath and say, OK, I cant dig myself out of this. Ive been lost so many times, I get off the road of purpose and I try to be something Im not. I gasp for air.

In Jim Collins bookGood to Greathe mentions three questions that you need to ask yourself:

1. What am I most passionate about?
2. What can I be the best in the world at?
3. Now, how can I make money?

As T.S. Elliot said, Arrive where we started and know the place for the first time. Why did you build this business? Think about the difference you were trying to make.

In your book you discuss Stewards of Purpose. What does this mean?
If youre a purpose-based leader, youre the steward of the companys purpose. For example, Southwest Airlines was founded on the premise that they were going to serve the underserved. Thats not some sort of social movement--it was simply recognizing that only 15 percent of the population had ever flown. So, Herb Kelleher (co-founder, Southwest Airlines) was an entrepreneur in 1971 who said to me, I think Ill niche myself at 85 percent of the business.

Entrepreneurs do this instinctively--if you build a business, you dont go out and serve the people who have already been served, you find the underserved market or a market that needs you.

As a steward of purpose you have to intimately know your companys purpose so you can champion it and not violate it. Ive seen many companies that start out with great purpose, and then they get a new leader who says, I think Ill just tweak this purpose thing. Dont tweak it. When you tweak it, you destroy it.

Think of your business as your land or your family--always protect it at all costs.

Excitement often gets lost in the daily grind. How can entrepreneurs ignite that passion again?
There are a couple great ways to ignite the passion back into your business. Herb Kelleher of Southwest once said to me, Roy, I want you to remember one thing: Take the competition seriously, but not yourself.

When you think, "Woe is me and woe is everything I do"--get the hell over it, take some yeast and lighten up. Its only business. Business is a game of life--its tough, its up, its down. When things go wrong, youve got to understand that this is not the end of the world. It might be the end of a cycle, you might lose a little money, you might have to lay some people off, but this is the time to take a deep breath and reignite your passion.

Life is here to be enjoyed. We start believing that making money is why you make a difference. Go back to making a difference and youll be more thrilled than youve ever been.

Why did you start your advertising agency Idea City?
We started the business at the University of Texas a long time ago--we had three goals:

1. Stay together
2. Stay in Austin, Texas
3. Make a difference.

Now, that doesnt give my adverting clients much validation of our talent. The thing is, when we builtIdea City, we decided that we were going to make a difference. In the process of this journey, weve done whatever it takes to build our clients businesses so they can fulfill their purpose--were being the best in the world at purpose-based branding.

When you enter Idea City, its like a Willy Wonka Factory for ideas--its eclectic, its come-as-you-are, its the idea that nobodys too good and everyones good enough. Were in the business of creating things that werent there before. Idea City charges you when you walk in--its full of young ideas and young people. At the end of the day, when were at our best, we help people fulfill their purpose--and we get paid for it. We get paid for making a difference. When were fulfilling our purpose, money comes and so does self-gratification.

Going forward, what role do you think entrepreneurs will play in the rebuilding of our economy?
For entrepreneurs right now, there is light at the end of the tunnel--its not a train. I believe that when the dust settles on this economic Armageddon, theres going to be a revolution of entrepreneurs building organizations based on purpose.

Millennials are going to lead the way and say, I no longer want a job, but there is work to do. I think its going to be the greatest renaissance--if the federal government doesnt spend all the money fertilizing dead trees. At some point entrepreneurs, young and old, will be in full bloom when spring arrives.

But, it will be different because there will be companies and leaders who are actually in the business of making a difference--thats the renaissance. It will be the new age of entrepreneurship based on purpose.

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