Most parents at some point give their kids a lecture about the importance of not getting caught up hanging with the "wrong crowd." The well-meaning warnings come because our parents know how closely our actions (and at times inaction) are tied to the people we invest our precious time in.

The idea that the people you surround yourself with have a profound impact on your success and career is echoed by two of the world's richest people, Bill Gates and Warren Buffet.

Buffet, who has been close friends with Gates for nearly 30 years, advised students at Columbia University to be selective about who they included in their inner circle:

You will move in the direction of the people that you associate with. So it's important to associate with people that are better than want to associate with people who are the kind of person you'd like to be.

Bill Gates has long been a proponent of this approach. In fact, because he was so protective about who he spent his time with, he and Buffet almost didn't meet. Gates recounts that he didn't think meeting Buffett would be a real value-add, because he thought he just "bought and sold pieces of paper," and didn't think they'd have anything in common.

But Gates notes he's glad he was wrong about his initial assumptions about his friend, as he wrote about the night they met:

I think the date stands out in my mind so clearly because it marked the beginning of a new and unexpected friendship for Melinda and me--one that has changed our lives for the better in every imaginable way. 

Warren has helped us do two things that are impossible to overdo in one lifetime: learn more and laugh more.

Far too many take a lackadaisical approach in cultivating a network that enables them to be the best version of themselves. As a result, the people in their squad let them compromise on their dreams, or contribute to them getting stuck in a rut of small thinking. No bueno.

Don't let that happen to you. Follow Gates' and Buffett's advice, and be intentional about cultivating a network that feeds you in deeper ways.

Here are four ways to evaluate who you spend your time with. As you make decisions about who to let into your inner circle, make sure they do at least one of the following for you.

1. Inspire you.

The people in your world should be doing cool things that make you feel proud of them. The work they are doing, and even how they live their lives should show you what is possible. The example they set should serve as a compass that helps guide you in the direction you should go. 

We are limited by our own experiences and frame of reference. As such, we need people in our lives who will stretch our minds, experiences, and perspectives in new ways. 

My business coach does that for me. He has opened my eyes to new opportunities that have heavily shaped the way I build my business.

2. Push you outside your comfort zone.

Doing what is comfortable may make you feel good in the short-term. But staying in your comfort zone for too long will stifle your growth and do you more harm than good.

I shared my three business goals for the year with a colleague, and he pushed me to make them bigger. He thought I was sandbagging and challenged me to stretch to reach a target that made me feel uncomfortable.

As a result of his push, I'm now working toward reaching that "uncomfortable" goal. The fun part is, it actually feels attainable as I dig in working on the strategy I've mapped out to reach it.

3. Hold you accountable.

I'm in a mastermind group with some friends. In December we got together and mapped out our business goals for the year and walked through our plans for how we'd accomplish them. Each month, we have a scheduled call where we talk about how we're tracking toward our individual goals. 

The people in your network will support you in your quest to be great. They won't let you take the easy way out. And they will hold to your word. 

4. Make you feel like you belong.

Business is about belonging. And you'll do your best work when you spend your time with people you know have your best interests at heart, and will give you the freedom and space to be fully you.

If you don't have a crew of people who make you feel like you belong, you'll have a tough time creating an environment for your team and your customers that makes them feel that way.

Spend time with people who bring out the best in you.