There are so many different people in your life with whom you share relationships: friends, parents, siblings, coworkers, your accountant—but the relationship you share with a business partner involves some unique aspects. And for that reason, it can’t just be anybody.

To me, a business partner is a trusted, value-adding ally who will dive in head-first with you and not come up for air until the time is right—as opposed to someone you’d interact with on a purely transactional basis. When choosing a business partner, I focus entirely on character. This person must demonstrate the following values and traits:

See also: Never pick a business partner based on their skills alone

A giving nature
Seek out someone who understands the concept of “givers gain,” by giving to others, you get in return. This person is genuinely and deeply interested in your personal success, even when you’re not around. When you’re busy, it’s easy to turn interactions into transactions, but a real partner actively focuses on your success even in the dry times. They’re willing to share their network and resources in the interest of symbiotic gain, not just hoping to dive into yours.

Complementary skills
Generally speaking, there are “fast twitch thinkers” and “slow twitch thinkers.” Some offer great answers on the spot (fast twitch), while others take much longer to arrive at an idea (slow twitch), but often consider more of the decision-making landscape. Know your personal style and seek out partners who complement it. When these two styles of problem solving combine, the result is much greater than the sum of your parts.

See also: Business lessons from Iraq: How to create a dynamic team

A clean slate
Look for someone with a proven track record of other long-term relationships. As the old adage goes, trust — but verify. Anyone who is not afraid of letting you access his or her past has nothing to hide. It’s one thing to find a value-adding partner, but it’s something entirely different to find someone who will be that partner for the long–term.

When I launched and grew my agency, I turned to developer and engineer Ben Nadel — now CTO of InVision — because he exhibited all the qualities I was looking for in a partner. Companies with more than one founder are statistically more likely to succeed, thus why I split the agency in half when I asked Ben to join. It turned out to be one of the best investments I’ve made for InVision.

When it comes to partnering up, it’s important to consider a persons professional background and accomplishments, but really focus on character. An individual with a stellar professional track record won’t get you through tough times or help you create a well-founded culture, but an individual of exceptional character will.

Read all responses to the Leadership Insider question: What do you look for in the ideal business partner?

Dolby CMO: What Star Wars taught me about finding business partners by Bob Borchers, senior vice president and CMO at Dolby Laboratories.

The quickest way to sabotage your new business by Jim Yu, CEO of BrightEdge.

How to avoid picking the wrong business partner by Ryan Harwood, CEO of PureWow.

3 signs you need to ditch your business partner by William Craig, founder and president of WebpageFX.

The most important relationship you will make in your career by Nirav Tolia, CEO of Nextdoor.