Forget those casually idyllic workplaces you hear about, with their flip-flop-wearing CEOs, their pingpong tables, their free catered lunches.

Frills are fine, but according to management experts, the elements of a happy workplace are more fundamental: quality of management, pay and promotion opportunities, overall workplace culture, job flexibility, a sense of helping make the world a better place. Oh, and an occasional picnic or party doesn’t hurt. “Different things are important to different employees,” said Teresa Rothausen-Vange, a professor of management in the Opus College of Business at the University of St. Thomas.

AdvisorNet Financial must be doing something right. Along with 18 other companies, it has ranked among the Star Tribune’s list of Top 100 Workplaces for each of the four years the paper has been commissioning the research.

“I knew when I first interviewed that this is where I wanted to be,” said Jill Hardie, AdvisorNet’s vice president for administration. Working there confirmed her initial impression that the environment is “supportive, positive, helpful.”

The company maintains that reputation in a variety of ways, including annual employee-appreciation picnics, extra days off in summer, and transparency about the company’s financial health and progress.

“We run the company in a way that [if] we were in the shoes of any of our employees, that’s how we’d want to have it happen,” said Daniel May, AdvisorNet’s president and CEO.

Happy workers aren’t just pleasant to be around. Employees who feel emotionally committed to their company and its goals “are more motivated and productive,” said Victor Lipman, a former Fortune 500 executive who writes about management for publications including Forbes and Psychology Today.

Yet, in a recent national study by Dale Carnegie Training, only 29 percent of employees said they felt fully engaged. More than a quarter were outright disengaged. Findings in research by the American Psychological Association’s Center for Organizational Excellence were similarly dismal, with majorities of employees saying they felt underpaid and unheard, and only about half feeling valued. Meanwhile, U.S. businesses reportedly lose $11 billion a year to employee turnover.

So, how to run a happy workplace? We turned to a group of experts — leaders from some of those 19 companies who’ve made the Top Workplaces list each year — and asked their secrets for engaging employees:

Give them autonomy

At Keller Williams Realty, councils of agents run each of the company’s individual offices. “We believe the agent is the center of all things real estate,” said Todd Butzer, Keller Williams’ Edina-based regional director. “We listen very, very carefully to what it is they need. We don’t issue directives to them.”

Plunkett’s Pest Control also trusts its employees on the job, said President Stacy O’Reilly. “In some companies, the quality control departments want to catch you doing something wrong. That’s not our style. We’re supporting them and helping them instead of watching them and checking on them.”

Keep them informed

In 2010, Tactile Systems Technology faced a cash-flow problem, and its leaders had to ask employees to take a substantial pay cut. Yet that same year, the employees rated Tactile one of the top workplaces in Minnesota.

“We promised that if we hit our plans and got back on track, we’d pay them back,” said Jerry Mattys, CEO of the company, which supplies equipment for in-home medical treatment.

Apparently, the employees trusted their bosses, thanks to a policy of openness regarding finances and progress, Mattys said. Sure enough, the company kept its payback promise and has since almost doubled in size.

Minneapolis marketing firm Periscope holds quarterly off-site meetings for all its employees, where leaders “share the financials, share our vision, and share what our challenges are,” said CEO Greg Kurowski. He opposes “the mushroom theory of management,” which he translates as, “Leave them in the dark, (er, fertilize them) and hope they will grow.”

Help them make a difference

Employees of Right at Home, which provides in-home services for seniors, can see for themselves how their work improves people’s lives. “The 92-year-old man whose wife has Alzheimer’s can maintain some sense of sanity, get some respite, get out of house,” said owner and CEO Paul Blom. “The 87-year-old woman who can’t any longer get down [to the] basement to do her laundry … we’re allowing her to live where she wants to live, in her home.”

Similarly, employees at Gillette Children’s Specialty Healthcare work with “children who come to us in wheelchairs, and because of the expertise we can bring to them, they are now able to walk,” said President and CEO Margaret Perryman.

Of course, not all industries intrinsically offer that level of altruistic reward. But some achieve a similar goal in a different way, by encouraging employees to volunteer for good causes. For example, all Werner Electric employees get one day a month of paid time they can devote, on their own or in a group, to a favorite service project — coaching a Little League team, adopting a park, packing meals for the hungry — said President Ben Granley.

Compensate them generously

Apparently money can buy happiness, at least in the workplace. At Graco, which provides pumps and spray equipment for industries, every employee from the factory floor on up receives stock options. And with the company’s stock recently at an all-time high, “there’s just a buzz in the place,” said David Ahlers, vice president of human resources and corporate communication. “Just intuitively, imagine how you feel about something when you own it, vs. when you work for us.”

Noran Neurological Clinic boasts “a fabulous benefit package,” said Suzanne Smith, human-resources manager. They also enjoyed bonuses at the end of 2012 “because the physicians really wanted to show how much they value the support of the employees.”

Show them a good time

The 80-plus employees of SafetyCall International/Pet Poison Helpline work on serious matters: calls from consumers about interactions with potentially toxic household products. But they also make a point of having fun. They hold an annual holiday party and a summer party with a lawn-bowling tournament. They celebrate anniversaries, engagements and weddings, get together for dinners and plays and wine tastings.

“We all like each other a lot and enjoy hanging around each other,” said CEO and partner Leo Sioris.

Blom, of Right at Home, takes his entire workforce out to the Chanhassen Dinner Theatre every year.

“It’s a sizable bill,” he said. “But at the end of the day, weighing the benefit of doing that vs. the cost, to me it’s just a no-brainer.”