As baby boomers retire, employers will feel the sting of a tight labor market. But boomers who choose to continue working could help fill some employment gaps.

Baby boomers—the largest generation in American history—number approximately 76 million. If they make a mass exodus from the workforce, the labor crisis will be even more severe than predicted.

But many boomers are indicating that they’re willing to continue working for many years to come.

“It’s expected that the baby boom generation will redefine retirement, because many plan to continue working in their later years,” says Deb Cohen, vice president of knowledge development for the Society for Human Resource Management.

Just last year the number of self-employed Americans 55-and-up rose 12.6 percent, to about 2.3 million, according to U.S. Bureau of Labor Statistics. Some of those leading-edge boomers are finding work as business consultants and returning to their old employers as independent contractors.

Other boomers will re-enter the workforce because early retirement fails. Their savings may have vanished during a down economy. Leisure retirement becomes boring than fulfilling. They miss the camaraderie of the workplace. They’ll look for jobs that offer more personal meaning than their original careers.

Whatever their reasons for returning to work, boomers are showing their willingness to remain on the job in some capacity. Small businesses that react to that trend by retaining or re-hiring boomers will have a leg up when the labor shortage hits full force.

“Unless companies find ways to retain aging baby boomers’ skills and experience, productivity in many organizations is bound to suffer,” says Howard Muson, author of The Conference Board’s 2003 report “Valuing Experience: How To Retain and Motivate Mature Workers.”