Call it a hat trick: for the first time in the 15-year history of Fortune's Best Companies to Work For list, we have a three-time champion, as Google reclaims the top spot for workforce happiness (it debuted on our list at no. 1 in 2007, and stayed there in 2008). We've had a couple double headers before -- Container Store, SAS and Edward Jones have all clinched the no. 1 spot twice -- but Google this year marks the first three-peat.
And while the perks of the Googleplex are epic -- everything from bocce ball to a bowling alley, from free food to free laundry -- what set it apart from the competition was one clear thing: its scores on our employee Trust Index, a blind survey of random employees that asks them about their general job satisfaction, attitude toward management, and sense of employee camaraderie.
It's this subjective stuff -- how employees really feel about their job and their workplace -- that makes up the backbone of our survey, which we conduct in cooperation with the Great Place to Work Institute, and of the list itself. Sure, the size of the swimming pool and the company match on the 401(k) plan matter, and we track those easily quantifiable things (you won't find a more complete recreational facility than the one at Qualcomm, for instance, and the holiday party at Salesforce.com is truly epic). But this list is a measure of employees' overall satisfaction with their jobs and the companies they work for -- which, smart CEOs will tell you, is worth its weight in gold.
Indeed, even in a tough economic climate, rather than cutting back on these niceties, the heads of the companies on our list know that investing in building and keeping a loyal workforce pays dividends. The voluntary turnover rates of companies on this list are astoundingly low; the lowest, SAS, is just 2.2%, but consider the rates of Intel (2.3%), General Mills (2.6%) and American Express (7%) -- and compare these figures with the corporate world at large, where rates in the 20s and higher are not uncommon, even in a rough job market.
So while the fitness facilities might help attract the best people, it tends to be the culture that keeps them. Who are this year's Best Companies and what makes them so great? Check out the top 20 companies to work for in the gallery below, and view the full list on CNNMoney.
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