I was talking to one of my friends who went to an Ivy League business school.

She told me, “On the first day, our professor told us to look around the room. He said: These are the people you will work for, the people who will work for you and the people with whom you will build a new world of work. This class is about learning, it’s also getting to know each other and building your network.’”

When she told me that, I thought, I wish someone had given me that advice when I was younger. I went to a state school. I enjoyed the experience and received a fine education (my school even won the SEC championship — Go Dawgs) But “building a network” wasn’t really talked about, at least not in the circles I ran in.

In fact, I often viewed my peers as my competition. Only some of us would be at the top of our class. Only a few would be sought out at the senior job fair.

I took that mentality into my first job, too. After college, I went into sales at P&G. I had a territory in Georgia spanning across a quarter of the state, calling on grocery store managers, with the goal of getting more shelf space for P&G.

It was crystal clear, at the end of two years, only a few of us would be promoted to sales manager. Fewer people would make it to regional. Only one of us would go on to be the future VP of sales or CEO of P&G (Spoiler alert, it wasn’t me).

I spent the first few years of my career overly focused on the near term. It was a mistake, one that countless young professionals (and many seasoned leaders) are guilty of as well. We let our ambition and enthusiasm default to competitiveness, instead of channeling it toward camaraderie.

Here’s what I wish someone had said at my first job: Look around the room. The people you’re sitting next to will become CEOs, founders, leaders and breakthrough thinkers, both here and in other organizations.

These people aren’t your competitors, they’re your peers, and they can be the best network in the world. Build relationships, stay connected and cheer for each other.

Later in my career, many people left P&G, myself included. We did go on to become executives, investors, authors and founders, all over the world. I’ve kept in touch with some of my entry-level class at P&G but not as many as I should have.

Here’s how to keep yourself from making the same mistake (even if you’re a few decades into your work life):

• Stay connected when you change jobs. When we work together, the cadence of daily business forces us to communicate regularly. When we change jobs, it’s often like people fall off the face of the planet. Don’t let that happen to you. LinkedIn is a huge leg-up in this (and certainly wasn’t around when I was starting out). Even outside of LinkedIn, exchange (not work) email addresses, phone numbers or at the very least, let each other know about your “next move.”

• Be (authentically) happy for them when they succeed — even if they succeed before you. There is not a limited pool of success to be had, nor is there a deadline for creating it. Everyone is on their journey. When you can tamper your competitiveness into authentic joy for your peers, your entire relationship changes. They feel it and it creates a circle of goodwill that always comes back to you.

• Don’t be afraid to share your success (and challenges). To build relationships that last, you need a level of depth. If your conversations are back and forth — “hope you’re doing well” — don’t be surprised if not much comes of it. Instead, dig into the wins and setbacks you’re having. Ask about theirs. Don’t be afraid to pull on each other for advice.

Your fellow high-performing peers aren’t your competition, not in the long-term at least. Sure, maybe only one of you will get promoted at the end of the year, but each of you will build impactful, fulfilling careers. Stay in touch, cheer for each other, and know, that the world is smaller than you think.