The road to taking a business from idea to actual business is a long one. For some small business owners (SBOs), one of those stops is finding a perfect co-navigator in a business partner.

But you don't want just any partner. You want the Spock to your Captain Kirk or the Watson to your Holmes. That's no small task. You have to find them and interview them. Then comes maybe the hardest part: making the final decision and determining if they pass "Is this the one?" test. Here are five key questions to ask yourself before picking a partner-in-success.

1. Do they share my passion for this idea?

Launching and running a small business isn't easy. It requires money and time, and will come with its share of speed bumps from which you'll need to protect it. Throughout it all, passion will push you forward during tough times. You need a partner who shares that drive.

Shared enthusiasm fuels ambition which, in turn, fuels success. So, ask potential partners what excites them about your business idea, where they'd like to see the company in five years, and what they'd look forward to in terms of working with you. See a twinkle in their eye, and enthusiasm in their voice? You may have found the right partner.

2. Will they challenge me and speak up when I'm wrong?

Nobody is always right. That doesn't change when you become the boss of your own business. You're still human like everyone else and therefore susceptible to mistakes, or bad ideas lurking in your blind spots. Except now those things can mean business disaster. That's why you want a partner who will speak up and challenge you, not someone who will agree with you all the way to failure.

To ensure your potential partner is someone who won't be shy about (respectfully) challenging you for the business' benefit, you can ask them if they'll be comfortable doing so during interviews, but also ask them for references. Prior associates can tell you if your potential partner practices what they preach.

3. How much will they give to the business?

While money and established equity division is important with a partner, there's another kind of giving that's important. You don't want someone who won't put in the work, but someone who will contribute resources, contacts, time, effort. A partner who gives themselves fully to the business will ensure its success, because they won't only worry about getting collective glory - they'll contribute to it.

How do you determine if a potential partner is giving? Ask questions like "What can you bring to the company?" and "How hands on will you be?" Be sure to crosscheck their answers with their references too.

4. Are we a personality match?

The relationship between business partners isn't unlike romantic ones. Chemistry, compatibility, and a connection are all vital for successful team-ups. After all, a business partner is someone you will be potentially committing to for many years of both good and rocky times. You need someone you like and can tolerate for that long.

Be sure to spend some time with candidates in a casual non-stuffy interview setting to get a better sense of how you'll get along, but also consider investing in personality tests which can help assess your personality types and your potential compatibility.

5. Do they complement you?

While compatibility is important, it's worth remembering there's a reason no baseball team is made up entirely of pitchers with the same temperament. A good team consists of players who complement each other. You need a partner who will bring talents and skills you lack, to round out what your business can offer.

If you are introverted and terrible at accounting, you may need to look for an extroverted numbers pro who's good with balance sheets. Think of a partner as the yin to your yang, who will round out the range of talents your business will need to succeed.