Not long ago, many employers looked askance at older workers, figuring they lacked the drive and imagination of their youthful cohorts. And besides, went the reasoning, younger people would work for less money.

Times are changing. Most businesses today are starting to view the mature worker as an essential commodity. The reason stems less from humanistic concern, and more from changing demographics: Workers are getting older and their replacements are getting scarcer.

In their drive to find quality workers, employers are being pressured by competing forces. First, people born at the close of World War II are now eyeing golf courses and swimming pools in Florida.

"We are facing a huge exodus of people from the work force as the baby boomers retire," says Ian Jacobsen, a Sunnyvale, Calif.—based workplace consultant.

Normally, one would expect younger prospects to rush into the vacuum. But the baby boomers who are now retiring were responsible for the rapid population growth that has begun tapering off. The result? Fewer younger people to fill the employment breach.

But that's not all. The downshift in the population engine is occurring at a time when a generally healthy economy has just about tapped out the talent market.

"We are living in the fullest employment era we have ever had," says Mel Kleiman, president of Humetrics, a Houston-based consultancy. "And we cannot afford to lose any workers. The reason is that women, who used to provide the supplemental work force from which employers could pull, are now at full employment as well."

All of these forces are coming together to increase the demand for older workers. We are entering a period in which the highest growth rate in the workforce will be among individuals aged 55 to 64. By 2015, according to the American Assn. of Retired Persons, one in every five employees will be at least 55 years of age. That's an increase of 10 million people in an age group which now accounts for 14 percent of employees.

Like any commodity, older employees are getting more valuable as they get scarcer. What can you do to keep your own? Here's what workplace psychologists say:

• Step #1: Eliminate stereotypes. Start by making sure your own supervisors worship no false gods of youth. Everyone must come to a fresh understanding about the value of mature employees.

"Employers will have to change their attitudes toward older workers," says Harriet Hankin, president of CGO Consulting Group, Malvern, Pa., and author of The New Workforce. "Researchers have discovered no evidence of a linkage between age and job performance. Indeed, it turns out that older workers have a stronger commitment to quality, experience lower turnover, take fewer days off, are not as tardy, and have excellent judgment based on years of experience."

And recent studies by the National Council on Aging found that in comparison with their younger counterparts, older workers had a higher level of commitment to the organization.

• Step #2: Motivate older workers. While younger workers may often be motivated by high salaries and the possibilities of advancement, these may not be the primary concerns of your mature workers.

"Older workers need to feel respected, appreciated and supported," says Jacobsen. "While these elements are keys to success with all workers, they are especially important when people are no longer working strictly for economic reasons. When work is competing with family interests and leisure pursuits, the psychic rewards become paramount for retention and motivation."

But if money does not motivate many older workers, what does? Best way to find out, suggests Kleiman, is to ask. Try a straightforward question such as, "Why do you still want to work?"

Be prepared for a surprise answer, and a resultant change in your motivational tactics. A survey by the AARP found that workers older than 45 most desired a friendly work environment (94 percent); respect from coworkers (90 percent); opportunities to use their skills and talents (94 percent); to do something worthwhile (91 percent); to learn something new (88 percent); to help others (86 percent) and pursue something they've always wanted to do (75 percent).

Given those motivations, you may hear responses such as, "I want to make a difference in the world," or "I don't have any outside interests," or, sometimes, "I want to work 30 hours because I have outside things to do."

Those answers suggest fundamental differences in motivation that you need to understand. For example, an individual who wants to leave a good mark on the world might be motivated by assignments to mentor younger employees in areas such as good communications skills, winning sales techniques and productive work habits.

After an interval of time, find out if the worker is getting the rewards desired. Make a point to return to the subject of motivation time and again. Feedback from workers will provide valuable clues on techniques to interact with the worker and offer incentives that motivate them to stay with your business.

And don't overlook mentoring as a way of boosting workplace performance and job satisfaction. Successful managers, says Hankin, understand that the generations can mentor each other.

"We have found, for example, that the World War II generation matches nicely with the 'millennial' now entering the workforce," says Hankin. "Younger workers can train older ones on newer software systems while older workers can provide a sense of history and judgment and wisdom in solving problems."

• Step #3: Introduce flexible policies. Both flexible work schedules and phased retirement can work well, says Jacobsen. Older workers who want more time with family or outside interests may welcome part-time schedules which allow the retention of employer-sponsored health insurance. (Note: Be sure to clear any policy changes with your attorney to avoid any appearance of age discrimination.)

There are other ways to introduce age-friendly flexibility. Flextime allows workers to start their eight-hour workdays at any hour. Job sharing allows two employees to share the same position, working with each other to coordinate schedules. Short-term projects and special assignments allow individuals who wish to retire to continue contributing to your business.

• Step #4: Resolve conflicts with younger bosses. Conflicts may arise when older workers report to younger bosses. Move quickly to resolve these problems if they arise in your workplace.

The younger supervisor should invite the older employee to a private meeting to discuss friction and resolve the issue through mutual understanding. Communication is the key.

"There is no reason why older and younger workers cannot get along when they respect each other," says Jacobsen. "It is important to communicate your respect and care for the other person, and the fact that you want to improve the relationship. If this message comes across age usually melts as an issue."

Employers who fail to create work environments friendly to older workers will find them jumping ship for organizations that do. Don't make that mistake.