If you've ever participated in your organization's recruitment efforts, you know some of the topics you should never bring up in an interview—among them, salary requirements, sexual orientation, and politics. But there's one factor that seems to keep candidates from even making it to the interview process that's too often overlooked: age.

Workers 55 and older currently make up more than 20 percent of the U.S. workforce, according to the Bureau of Labor Statistics, and many of them will face discrimination while job searching and while working. In an AARP study, 64 percent of older adults claimed they've seen or experienced age discrimination in the workplace.

Here's how to make sure your organization treats candidates of all ages fairly, from recruitment to onboarding.

Post your jobs in places where older workers will find them. Along with large aggregators and niche job boards specific to your sector, consider posting your jobs on boards that cater to older workers. The American Society on Aging, for example, has a robust career center, and AARP has its own program called Life Reimagined for Work.

Explicitly welcome older applicants in your job postings and recruitment messaging. Many older candidates hesitate to respond to job postings because they anticipate age discrimination. Using terms like "fresh" and "new talent" in your postings suggests that your organization is only interested in young candidates. To encourage older workers to apply, include images and voices of mature people in your recruitment materials.

Older workers are often willing and able to be effective in a different position or role than they had held at earlier stages in their careers.

Keep age-related information out of screening materials, when possible. To help your hiring team avoid unintended age discrimination, consider removing candidate information like date of birth, photos, and graduation dates from screening materials.

Don't make assumptions about candidate motivations. Hiring managers often view older candidates as overqualified and dismiss them out of hand from the candidate pool. But an older worker may be an ideal fit for the open position. Instead of seeking a lateral career move, he or she might be interested in better work-life balance. Older workers are often willing and able to be effective in a different position or role than they had held at earlier stages in their careers, so make sure to pay close attention to cover letters and interview answers that provide context for what might seem like a non-lateral move.

When negotiating benefits, think flexibility. Retirement may be the most obvious benefit that you'd expect older workers to want to discuss. But older workers may be contending with situations in their personal lives—caring for grandchildren, for example, or dealing with eldercare—that make other benefits attractive. When offering a candidate a compensation package, find out what eldercare benefits your organization provides. Also, consider offering flexible work hours and remote work as part of your benefits package.

Create reverse-mentorships as professional development. A common misconception about older workers is that they can't—and don't want to—use technology effectively and are less productive as a result. In a recent report, Ageism and Bias in the American Workplace, the American Society on Aging points out that multiple studies show that older workers are just as productive as their younger counterparts.

To combat this perception and equip new hires with the tools they need, consider creating "reverse mentorships" in which older and younger workers pair up and trade tech trainings, for older workers, and career mentoring, for younger workers.

When you're recruiting for an open position, remember that candidates of all ages can add value to your organization—and that including older workers on your staff can boost your organization's ability to succeed.