For years I had a friend who kept suggesting he and I should start a cafe-book store together. It was tempting in a way--I loved the idea of a cozy place full of people reading, chatting, and sipping lattes. But I always said no. Though I enjoyed this friend, I knew he was always looking for get-rich-quick endeavors. He seemed to expect the greatest return for the least effort. Would he put in the long hours it takes to get a successful business off the ground? Unlikely. Would I wind up putting in extra hours to make up the slack? Likely.

That was an easy decision, but often it's not so obvious whether a friend, acquaintance, or co-worker would or would not make a good business partner. Yet it's not a choice you can afford to flub. Not only will picking the right partner affect your very livelihood, for a while at least, you will spend more time with him or her than you do with your spouse.

How can you tell if someone is "the one"? For the past 21 years, Bill John and Lain Hensley have been partners in Odyssey Teams, which creates leadership development and team building programs. Here's their advice:

Try before you buy.

Not every potential business couple has this luxury. But if you can, spend some time working together in the business before you both commit. In Odyssey Teams' case, John was already running the company.  Hensley attended one of its programs, became friends with John, and began helping out, first as a volunteer, then as a paid contractor. John promised a month's work, then a few months, then a few more.

Hensley had recently graduated from college and wanted to be a business owner. At the time, Odyssey Teams couldn't afford to pay either man a substantial salary, so making Hensley a partner was both a way to recognize his contributions and make sure that he stuck around. "He was just so helpful that it made sense," John says.

Share off hours.

John and Hensley's relationship was cemented not only at Odyssey Teams programs, but also while fly fishing, snowboarding, and building things together. "We're both project-a-holics and we like swinging hammers and building stuff," John says. It was during these extracurricular activities that they both learned how compatible they were.

Travel together.

Anyone who's ever taken a trip with a friend knows that there's no quicker way to find out just how well you do or don't get along. "Take a trip to the Grand Canyon and see who wants to stay on schedule and who's looking to go off and see the world's biggest ball of string," Hensley suggests.

You'll learn if you have a real connection, he adds. "When there's down time, do you have healthy conversations? Do you talk about how you want to change the world or do you turn the radio up? You can learn a lot about someone in a short time."

Look for matching values...

One thing John and Hensley learned in their off hours is that each brought the same high standards and energy to what they did. "He was a good fisherman and I was a good fisherman," Hensley says. "He would build something well and so would I. If we were going to run a race, we would both expect to do well."

That translated into a similar work ethic at Odyssey Teams. "We would both have the same high expectation for what we were going to give customers," he says. "And we can both work from 7 in the morning to 9 at night without complaining."

...But dovetailing skills.

If having similar values and expectations makes for a solid partnership, having different abilities makes for a successful one. "Now that I look back, I can see how perfectly Bill and I complement each other," Hensley says. "Bill is really good at Web stuff and financial complexity, where I'm more on the people side. I love the delivery but I don't have the patience to work through the detail side of the business."

Decide about decisions.

One of the most challenging aspects of any business partnership is determining how decisions will be made if the partners don't agree. John and Hensley learned this the hard way when they took on a third partner who had academic training in their area but turned out to be a terrible fit.

"If we were in a debate, he would reach a point where he would say, 'I'm doing it with or without you!'" Hensley recalls. "Bill and I would just look at each other. We couldn't process that. We were a team."

Mercifully, the third partner soon departed. But the experience taught John and Hensley the importance of creating a delineated decision-making process. "We're wrestling with that right now," John says.

Pick someone who's fun to be with.

In retrospect, both partners say, the fun was missing with that third partner. And it's the single most important element, they agree. "There has to be that X factor," Hensley says. "You need some of that friend side where you have a relationship that will survive whatever conflict comes your way. If it's just a business deal, then when those conflicts arise, the off-ramp will come up and you might make that choice."

"To me, it was all about character outside of work," John adds. "I realized that if I partnered with Lain it was going to be fun on this journey."

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