"What we think of mentors is wrong."

So says Linda Rottenberg, CEO of Endeavor, a global non-profit that supports high-impact entrepreneurs. "We think this older, wiser protector is going to shield us from harm," she adds. "We want nice--but we need someone telling us what stinks."

And she's right.

Contrary to the conventional wisdom, as Rottenberg notes in her forthcoming book Crazy Is A Compliment, peers--rather than wizened sages--are oftentimes the best people for dishing out a healthy dose of tough love. One study she cites found that relationships with peers "offer important alternatives to those with conventionally defined mentors." This research from Boston University's Kathy Kram and the University of Virginia's Lynn Isabella also found that peers can coach, counsel and provide critical information that supports entrepreneurs in handling personal problems and attaining professional growth.

But how do you go about finding the right peers to grow your business?

Work Alongside Them
Business founders have numerous venues to choose from where they can work with their peers, including a growing number of coworking spaces that feature professionals from a variety of sectors. These have been particularly helpful for startups during the earlier stages of their development. Thalmic Labs, for one, cycled through a few business accelerators while developing its gesture-controlled Myo device and worked alongside other tech-minded peers.

"It's incredibly valuable to have a network of people who have been through similar experiences to ask for advice and learn from," says Stephen Lake, co-founder of Thalmic Labs.

Those who are still students may find a match at certain college-based programs. For example, the Foundry business accelerator at the University of Utah focuses on fostering a peer-to-peer coaching style among its participants:

"We believe that a group of new entrepreneurs that are dedicated to helping each other grow their businesses can produce better results than high-class mentors or business professors," says Kyle Gray, who participated in two cohorts at the accelerator before becoming its director. "It's about creating a community and a culture that treats new entrepreneurs like they are already CEOs and hold them to the expectations that are typical of a CEO."

Meet Up with Other Founders
Some groups specialize in linking together like-minded executives. The Entrepreneurs' Organization, for one, matches individuals (based on a mentor's expertise and a mentee's goals) who then meet face-to-face once a month to strive toward specific business goals.

At JOLT, a Toronto-based accelerator, startup founders gather every other week, switch off their devices and discuss market challenges their ventures are grappling with. "You see the good, the bad, the ugly--the areas where they're struggling, and where they need to either source resources or get some expertise to the table," says Susan McGill, JOLT's executive director and co-founder.

"It's really hard work building a company, so I can't stress enough the importance of having that support system of like-minded entrepreneurs going through a very similar grind."

Consider Atypical Pools of Peers
Two words: social media. From Facebook and YouTube to Snapchat and Vine, the next generation is often ahead of the curve when it comes to adopting new technologies--and they can help businesses do the same. "Getting mentors younger than you is really important," says Rottenberg.

In some cases, so-called frenemies--think former rivals or perhaps even current competitors--might also share helpful advice or lessons from which you could learn. Some argue Larry Page, Google's co-founder, once pared back Google's growing suite of offerings following a visit with his Steve Jobs, who advised his rival to focus on fewer products and play to the company's core strengths.

"Your frenemies make good mentors because even if they're competitors they are dealing with the exact same issues," says Rottenberg, who writes about the rocky Jobs/Page relationship in her book.