Conventional wisdom tells us not to go into business with friends. I have every reason to believe and even perpetuate that advice. However, there are exceptions to every rule, or in this case nine of them.

Check out these stories of nine entrepreneurs who have successfully partnered with or hired friends, along with their advice if you're looking to do the same.

1. Check egos at the door.

Ego is a challenge in any relationship, especially in a friendship-turned-professional one.

"Working with close friends can work well, provided the right expectations are set. At Unified our culture demands checking your ego at the door, regardless of position or tenure," says Joshua Backer, co-founder of Unified Social. "Not all of my friends would be a good fit for our culture, and that's fine, but those who have been a fit understand that friendship isn't a substitute for accountability. Hiring or starting a company with friends is not a choice I would make lightly, however the implicit trust and chemistry is invaluable if you can make it work.”

Takeaway: Lay out clear expectations for the company culture and work environment, and be sure your friends turned hires fit personality-wise for that. Check your egos at the door!

Related: How to Hire Friends Without Destroying Relationships

2. Share a common vision.

“I've known my friend Neil Gadhok for more than six years. We worked at multiple companies together before starting yeeldr in 2013. We are the type of friends who can finish each other's sentences and it was that chemistry that made us over look the common phrase 'don't do business with friends or family,'" says Curtis Smith, CEO and co-founder of yeeldr. "Some individuals have an unspoken bond and trust level that other people buy into -- we had that. If I was to give one word of advice to other entrepreneurs who are looking to work with their friends, it would be to make sure that you are 100 percent in sync with what you want out of your business's future. Don't assume that just because you agree on most things, that you both want the same goals for your company.”

Takeaway: Leverage the chemistry you have with friends, and be certain that you have a shared vision for the businesses’ future.

3. Share a common passion about your product or service.

You can see past a resume with a friend and better understand his or her values and interests.

"I've always valued honesty and perseverance much more than experience. When I approached my friend about becoming a partner in Fortune Cookie Advertising he agreed within seconds," says Shawn Porat, COO of Fortune Cookie Advertising. "The partnership has brought us a lot of great memories and successes. If you have a trustworthy friend who is passionate about your project do not let the opportunity pass you by.”

Takeaway: Make sure there is alignment around being passionate about the work.

4. Leverage historic trust and knowledge of communication styles.

“When we looked for our first hire at LabMinds, I ended up sending the job description to a close friend from university to distribute amongst his peers. He decided to apply for the job himself, and since then has joined us at the helm of LabMinds," says Dr. Jochen Klingelhoefer, founder and vice president of product at LabMinds. "Why? On top of being exceptionally qualified, the long friendship provided both a solid trust base as well as well-understood communication styles -- two factors whose importance in executive teams can't be overemphasized.”

Takeaway: Friendships are underpinned with trust so utilize that as well as your historic understanding of how to best communicate with one another.

5. Only hire your friend if you’d hire them regardless of your relationship.

It’s easy to consider hiring someone because you know them and they’re available, but be certain that you’d hire them only if they are the best fit for the position.

“When my best friend's brother became addicted to prescription painkillers, we sought out to provide a solution in preventing the ease of access within the household to medications. The three of us co-founders were college friends prior to banding together in our endeavor," says Zachary Burkes, COO and co-founder at Safer Lock. "Our relationships and company dynamic work because we balance each other out. One is the technical engineer, the other the savvy salesman and the last one is the operational leader. Outside of our own four walls, we are very different and it works to our benefit in running a company.”

Takeaway: When you have a shared experience that leads to the creation of company around a problem in the marketplace, be sure you’re working with people who would be the best fit for the job regardless of your pre-existing relationship.

Related: The No. 1 Reason You Should Hire a Family Member

6. Start with small projects first.

Most people don’t jump into a marriage without dating first. Why would you then not do that for a business partnership?

“I’ve worked with my longtime friend Murray Newlands for several years now. I recommend that anyone in this situation start by working on a project or two together," says John Rampton, founder of Due. "This makes it easier to get to know if you’ll work well together. Much like a spouse, this is a person that you’re going to be working countless hours with on a project that will have ups and downs, so make sure you don’t get into a business relationship with someone you don’t trust. “

Takeaway: “Date” before you “get married.” Start with smaller projects first to test the waters before going into a full-fledged partnership or offering a job.

7. Set clear boundaries between work and play.

One of the closest friendships one can have is with your spouse.

“When I started Mizzen+Main three years ago solo, I knew it would always be something my wife and I would pour all of ourselves into. Jen helped keep us afloat as a family for a few years with a 'real' job until we grew to a point that I needed her to come on full time," says CEO and founder of Mizzen+Main Kevin Lavelle. "We have had to keep our eyes wide open and lay some basic ground rules separating work and home life, which is always tough, but truthfully neither of us could imagine not working together at this point. We respect each other’s decisions and know that at the end of the day we are trying to build the next great American brand together!”

Takeaway: Set boundaries to define when work ends and your personal life begins. This won’t be seamless, but sometimes simply setting the intention is better than not doing so at all.

8. Have counter-balancing strengths.

Individuals don’t often possess all the skills needed to found a company, so utilizing a friend who has opposite skills can be a great benefit.

“When David and I first met, it started off as a great friendship and eventually led to a very successful business, Executive SEO Inc.," says its co-founder, Kyle Gustin. "When picking a business partner, it's important you have someone working with you whose strengths offset your weaknesses. This allows you both to achieve your highest potential while minimizing any pitfalls you might encounter along the way. It's a recipe for great success.”

Takeaway: Look through your pool of friends to see whose strengths counter-balance your weaknesses.

9. The business come first.

"Make sure your decisions are still business decisions, regardless of friendship," says Tom McLeod, CEO and founder of Omni. "One of the hardest parts of hiring is trusting that while qualified, the candidate will actually rise to the occasion. Hiring friends solves this in two distinct ways. First, you trust them with your friendship, so hopefully that means you know you're getting a quality human. Second, you already understand how to communicate with them. Without the feeling-each-other-out grace period, a friend hire has the potential to make an immediate impact in the company."

Takeaway: Stay focused on what's best for your business. It's a bonus if your friends line up with those needs.

Related: How to Fire a Family Member in a Family-Run Business