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Everyone loves to talk about the leader. The CEO. The President. The Owner.

But what if the primary leader were only 50 percent of the success equation? If you ask Cameron Herold, the former COO (Chief Operating Officer) of 1-800-GOT-JUNK?, he'll tell you that the second-in-command is perhaps the most critical person in the company when it comes to sustainable growth and success.

In part, that's why Herold started the COO Alliance, which is the only educational group dedicated to the second-in-command. As he told me last month, "Entrepreneurs build companies, but at some point, they need someone who can run the day-to-day operations for them. It makes sense that sharing the load would lighten the CEO's burden. He can then afford to take a sick day or get a good night's sleep. It also allows them to focus their energies on the two or three things at which they excel and are uniquely capable of doing. Entrepreneurs are visionaries, but they often lack the detail orientation to get things done and in the right way."

How does he know? He learned by doing, when he took 1-800-GOT-JUNK? from $2 Million to over $100 Million -- in six years.

If that doesn't make the case for having a brilliant lieutenant at your side, nothing will.

So how do you hire a brilliant COO, or any key executive, that can give you the rocket fuel you need to take your business to the next level?

Herold recommends that, before you hire your key executive, you "be honest with yourself about what your weaknesses are and identify the areas of the job you don't love doing so you can find someone who has strengths in those areas and enjoys those aspects of the business." Therefore, saying you need a second-in-command is kind of like saying you need to learn something new. In this case, it's all about finding the unique abilities that balance out what you, as a leader, already have.

As an aside, this is the same yin-and-yang effect that Gino Wickman describes in his Entrepreneur's Operating System, from the book Traction. Gino calls it the "Visionary" and the "Integrator." This two-part leadership system repeats itself across many different schools of thought; and, since I've seen it work in my own experience, I know that COO selection is one of the most critical components to sustainable business success for any entrepreneur.

If you're at the point of needing a true second-in-command, here's how to hire right for your leadership type, and reap the rewards of a great supporting role:

1. Choose Experience

"To be clear," Herold explained, "you are looking for people with experience doing these tasks, rather than people who are merely qualified to do them." It's critical to hire someone who has demonstrated that they are capable of doing exactly what you need.

So how do you get such experienced candidates? Talented COOs aren't looking for a job -- the vast majority already have happy, wonderful, high-paying jobs. So, Herold recommends hiring an executive search firm to help you find the right person. It's a good example of spending a little now to get the right value later.

2. Look for Personality Fit

Because of how close the CEO and COO must work together, it is critical for both people to deeply understand each other beyond a casual and professional level. Herold pointed out, "as CEO, you have a lot to deal with, so the more your second-in-command can do to keep obstructions out of your way, the more you can focus on the bigger issues." If your COO is making more work for you, you'll never achieve the 1+1=3 effect you were pursuing in the first place.

3. Write a Killer Job Description

Once you find candidates, your job description will need to capture their attention and make them want to jump ship. Herold noted that, "when your ideal candidate reads it, he needs to be like, 'Heck yeah, I am all in.'"

Most importantly, be honest. Allow your true personality and culture to shine through, so that there are no surprises after the fact. Remember: The best COO for your company will inherently fit your personality and culture, which is what helps to engender trust in the first place.

4. Have Key Performance Indicators

When hiring a COO, build a "scorecard" that will tell you if that position is achieving the goals or not. At GEM, we use Key Performance Indicators for every new employee, and it's been a great way for both the employee and the company to understand the expectations and map out concrete ways to achieve them.

5. Trust Your Choice

The worst thing a CEO or owner can do is hire a brilliant COO and then get in the way. If you've vetted the position and the person properly, you must allow that person to take the proverbial ball and run with it. After all, the point of hiring that person is to have that person take tasks and projects away from you. Don't go running after those tasks after you let go!

At one of my first jobs in high school, I rose to become the second-in-command, and did my best to take tasks off the owner's plate. To echo Herold's sentiment about the closeness of that relationship, that owner is now my business partner in two of my companies. Fortunately, we both now have a second-in-command that is all of these things and more. He has allowed us the freedom to do what we each do best, consequently growing our largest company by more than 400% over the past three years.

So go out there and get yourself a brilliant supporting role. Once you do, you'll realize that the old adage also applies to business: It takes two to tango.