Now more than ever, you need the best investments you can find in order to boost your chances of retiring comfortably. Despite a turbulent market, young investors have plenty of time to ride out the bumps in the road and earn big long-term returns. But finding the time to do research to uncover top investment prospects can be tough.

That's why we asked four of our Foolish contributors to weigh in with their ideas on stocks that can help you retire rich. Here are their suggestions.

Brian Orelli:
Investors willing to take on more risk in the hopes of gaining higher returns can find it in biotech. But you need to be careful betting on binary events like clinical trial results and Food and Drug Administration approval decisions in a retirement fund where the permanent loss of capital is devastating.

A better approach to investing in the high-growth biotech sector would be to pick a company like Dendreon (Nasdaq: DNDN) or Human Genome Sciences (Nasdaq: HGSI), which already have drugs on the market. Sure you've missed out on the quick monster returns -- Human Genome soared some 6,300% from its lows -- but there's still growth left in them.

Dendreon is guiding for ramping sales of its prostate cancer treatment Provenge from $25 million in the fourth quarter of last year to about $175 million in the fourth quarter this year. Even with a slowdown to a less ambitious growth rate next year, Provenge should hit $1 billion blockbuster status quickly.

Human Genome is a bit further back in the growth curve, having recently launched Benlysta, so the company isn't offering up guidance just yet. But the demand would seem to be there, considering that Benlysta is the first medication approved for lupus in half a century.

Anders Bylund:
In order to buy a stock today and rely on it fueling retirement accounts decades away, you're really looking for a "forever stock." Becoming one takes several key ingredients:

  • An unassailable business moat.
  • Top-notch management.
  • A rock-solid financial platform.
  • And most of all, a core business that will still be relevant 20 or 30 years from now.

What about dividends? A company matching this pattern will get around to payouts eventually. Patience, young grasshopper.

I find all of the above in robotic-surgery expert Intuitive Surgical (Nasdaq: ISRG). The moat is protected by technology patents and FDA-approved procedures with freakin' lasers on their heads. It took several gutsy calls to get to that point, including the acquisition of Intuitive Surgical's only close competitor. In the last four quarters, the company generated more than $400 million of free cash flow and sits on more than $1 billion of debt-free cash and short-term investments. Machine-assisted surgery holds so many benefits for patients and surgeons alike that you have to believe it to be the only option at some point.

And thanks to those patents and a healthy dose of fresh R&D action, the only plausible way to enter the field today is by acquiring Intuitive Surgical. If that happens, you'll end up owning a buyout-boosted piece of some medical giant with the resources to pull off a $14+ billion deal -- and there's nothing wrong with owning some Johnson & Johnson or Medtronic as the boomer generation ages, either.

Tim Beyers:
Retirement funds aren't to be trifled with. But if you're young and have time to be aggressive with your money, I suggest betting on themes that have an above-average chance of creating value over a decade or more.

Cloud computing is that kind of theme. A wholesale shift to delivering processing power, storage, and software via the Web the way utilities deliver electricity via the grid is producing billions in revenue for the likes of and VMware (NYSE: VMW). The trouble is that these stocks boast triple-digit P/E ratios and could lose 50% or more of their value before doubling or tripling.

Fortunately, retirement investors needn't suffer with this sort of volatility. Google (Nasdaq: GOOG) and 8x8 (Nasdaq: EGHT) are cloud-centric, high-growth businesses selling at reasonable prices -- 19 and 35 times earnings, respectively. Those multiples buy Web-based technology that's reshaping advertising and phone service.

In Google, investors get one of the cloud's poster companies whose rich resources are now being deployed to take advantage of social and mobile advertising. In 8x8, investors get a popular and fast-growing suite of Internet telecom apps designed specifically for cost-constrained small businesses.

Either business could disappoint, of course. But if they do, it won't be because of needless speculation. Advertising and phone service are as relevant in this century as they were in the last.

Sean Williams:
At some point in the near future, I anticipate that investors will realize Apple isn't the only mobile powerhouse in town. Research In Motion (Nasdaq: RIMM) may not have the same pizzazz as the iPhone, but its primary product -- the BlackBerry -- still commands enough market share to take customers away from Apple.

Most investors have written off RIM as a lost cause, but its balance sheet tells another story. Having consistently grown in double digits and slated to grow at 17% over the next five years, this could be the growth stock younger investors are looking for. RIM boasts healthy cash reserves of $2.1 billion that it can use for future product development. More intriguingly, the almost $3 billion in free cash flow it generated over the past 12 months shows that the company has enough money to pay a future dividend.

RIM's loyal base of customers and its microscopic forward P/E of seven make it an intriguing play to set and forget in a long-term portfolio.

To keep these six stocks front and center on your radar screen, add them to your watchlist today.

What stocks do you think are the best for young investors saving for retirement over the long haul? Share your thoughts in the comments below!

With respect to the stocks they've written about, Tim Beyers owns shares of Google and 8x8, and Anders Bylund owns shares of Intuitive Surgical. is a Motley Fool Big Short short-sale recommendation. Google and Johnson & Johnson are Motley Fool Inside Value picks., Google, Intuitive Surgical, and VMware are Motley Fool Rule Breakers recommendations. Apple is a Motley Fool Stock Advisor pick. Johnson & Johnson is a Motley Fool Income Investor recommendation. Motley Fool Options has recommended a bull call spread position on Apple and a diagonal call position on Johnson & Johnson. The Fool owns shares of Apple, Google, Johnson & Johnson, and Medtronic. Alpha Newsletter Account LLC owns shares of Johnson & Johnson.

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