FORTUNE — A lot of young entrepreneurs are raising money from VCs and angels at sky-high valuations today. My question is, what are they really seeking? A pelt, or a partner?

By “pelt”, I mean an animal skin—a trophy, a head to hang on the wall that you can show your friends and say, “See that head on my wall? I killed a big old moose.” Only in Silicon Valley, the boast is, “See that story in TechCrunch? I just raised money at a really high price.”

Is this a good idea? I don’t think so. I worry that too many promising entrepreneurs today view fundraising as a means to securing pelts, and not true partners. And despite the new landscape for startups today—cheaper infrastructure costs, fast money, and a generally frothy environment that is boosting valuations—entrepreneurs who want to build lasting companies need real partners on their boards. The pelt decision may come back to haunt them.

The best opportunity to bring on a partner with unbending commitment to your company’s success is at your seed round or Series A. Just as your first few hires form the critical nucleus of what could someday be an exceptional team and company culture, your first board member should serve as the core of what should ultimately be a fair and supportive, but tough-minded and experienced board. Then, each subsequent funding round allows you to bring on another really great board member with a deep economic interest in your success, and the company’s.

At the early stages of a company, a board member should be a true “consigliere” to the CEO, committing his or her time and significant capital throughout the entire lifecycle of the venture. His or her contributions should be appropriate to the needs of the CEO and company at that time, and could include: helping with the product/market fit process; bringing his or her network to bear to find new customers, partners and hires; and encouraging the adoption of key values and critical business practices that will cement the company’s culture. As the company grows and scales, this trusted board member should proactively help the CEO navigate new challenges that arise, such as securing additional capital, refining strategy, strengthening and expanding the leadership team and keeping the team aligned and motivated. And, throughout, this person should serve as a highly available, safe “sounding board” for any concerns or doubts you have, including ones that you feel embarrassed to ask others or are inappropriate to ask your team. This contrasts to what board members offer at later stages, when things like encouraging the use of leverage or helping prepare the company for an IPO become more important. Obviously, you can’t do any of those later- stage refinements if you haven’t created the right foundation.

Entrepreneurs who choose a less-involved board early on can quickly get into trouble. Often, these entrepreneurs wind up raising too much money with unreasonable expectations, which can distort the whole company-building process. The unseasoned CEO might hire too many or too few executives at first, or take on too many initiatives. This dilutes focus. The CEO might over-promise and under-deliver to initial customers or agree to unfavorable terms when negotiating a high-profile partnership to get a high profile deal done. A trusted advisor could have helped avoid some, if not all, of these pitfalls.

Why don’t we hear more about these consigliere, or “lifecyle” investors? I think its largely due to the heroic myth of the lone-eagle entrepreneur that the media so loves. Similar to the pattern described in scholar Joseph Campbell’s Hero’s Journey narrative, the true entrepreneur heads out alone into the forest to achieve a great adventure—except this adventure is building a lasting company, like Disney, Apple, HP, GE or IBM. What the myth doesn’t leave room for is an experienced, trusted board member who is often instrumental in the entrepreneur’s success. What’s interesting is that most of the consiglieres I know love and respect this myth, too. They don’t have ego needs to be publicly recognized for their silent, yet important contributions—they’re not constantly blogging about them or Tweeting them out to followers. Sure, these investors want to make money. But the quiet knowledge that they were part of the company’s success (and generated significant wealth for the company founders and team while doing so), is just as, or more, important.

For this reason, trusted, involved board members are not cheap. You won’t see these investors fighting to win auctions run by entrepreneurs seeking the biggest pelt. They will also not make a decision after a single meeting; instead, they will ask to spend quality time getting to know you, your ideas and your values over coffees, dinners and in front of the whiteboard. And they expect you to do the same.

This may all sound hopelessly old-fashioned. But I’ve had the honor and privilege of seeing several of these partnerships in action—and I believe it’s a model that still applies to today’s companies.
My first experience with this magical CEO/consigliere dance was at Kleiner Perkins, after just a couple weeks on the job. John Doerr and his partners had invested in a brilliant, passionate, but unproven entrepreneur with a laugh that resonated through the elevator shafts at the company’s headquarters in Seattle. Jeff Bezos had picked John carefully and didn’t hesitate to tap John’s advice, network and insights. They spoke frequently, and as best I could tell, John strongly influenced Jeff to adopt a strategy of “get big fast” in the face of analyst skepticism. To do this, Jeff recruited a deeply experienced executive team, including critical early hires like Rick Dalzell, the former head of IT at Wal-Mart, and rapidly acquired new customers as the company racked up huge GAAP losses. Things obviously turned out OK for Amazon.

My second experience began in 2003 when Dave Strohm, a partner at Greylock Capital, introduced me to Lars Dalgaard, CEO of SAAS performance- management firm SuccessFactors. Dave was Lars’ consigliere: He had orchestrated the acquisition of three failed performance-management companies into a rebirthed SuccessFactors and helped bring in Lars at this time as CEO. Dave rolled up his sleeves, working closely with Lars to develop the core strategy for the business, recruit key early executives from his network (like tech-industry veteran Randy Womack, who ran operations at SuccessFactors), secure hundreds of customers and develop highly contrarian cash-compensation plans. Lars had a strong desire for his team to be rewarded with large cash bonuses for executing well above plan. I recall Dave saying to me at the time of my firm’s investment in the company that he made this promise to Lars, and he needed to know that I would honor it as the third board member. At first, I thought it was crazy. What is a small start-up doing committing large cash bonuses for performance above plan? Shouldn’t all the cash being generated by such performance be folded back into the business? Lars operated differently. Dave recognized it and had helped create an unconventional plan that met Lars’ goal while, at the same time, being good for the company. I ended up agreeing. And as Lars promised, the company shot the lights out on their booking and cash plan. (And in December, SAP bought the company for $3.4 billion.)

My third experience was in 2005 as an angel investor with Stella & Dot. Founder and CEO Jessica Herrin secured a trusted adviser in Michael Lohner after carefully scanning the market for experienced party-planning executives. Michael fell in love with Jessica’s vision and entrepreneurial grit, invested a significant amount of personal capital in the company and joined the board. He also believed that Jessica was on the right track with the company, but that both the product and sales team needed important adjustments. Working closely together while he assumed the CEO title for a short time, Jessica and Michael improved both of these pillars of the business very successfully, and Stella & Dot has become one of the fastest-growing firms in the Inc. 500.

If you’re a young entrepreneur, it’s hard to turn down a boatload of cheap cash and a promise of non-interference when you’re out raising money for your start-up. All of us have felt, at one time or another, that we have all the answers. But we don’t. My advice: Find a lifecycle partner you can trust and get him or her fully committed. You might wind up with a truly lasting company instead of a moose head on your wall.