Diversity and inclusion are hot terms in business today, but companies often focus on race only. What about age?

I receive many emails from readers asking about their working situation, and if my inbox is any indication, age discrimination is widespread. I get far more questions about age discrimination than any other form of illegal discrimination. An AARP survey backed that up when they found that nearly two-thirds of older Americans have seen or personally experienced age discrimination

You may think you're not discriminating against older people in your hiring and promoting, but it can happen under your nose without realizing it. Here are some examples of how your company may be discriminating against older candidates.

All entry-level recruiting is done through universities.

On its face, this seems fine. If the job requires a college degree and little or no experience, that's the perfect place to find people. But think about all those stay-at-home moms (and dads) whose kids have flown the nest and are interested in coming back into the workforce. Sure, they may have degrees that are decades old, but they may be perfect for your entry-level roles if you'll open up the recruiting.

You think (consciously or subconsciously) that new ideas mean young people.

We praise young people when they launch successful startups. You know why? Because they are the exception rather than the rule. The average age for a successful tech startup founder is 45. The United States considers you an "older worker" at 40. My Inc. colleague Jeff Haden reminds us that "a 50-year-old entrepreneur is almost twice as likely to start an extremely successful company as a 30-year-old."

And remember, even if you have all the ideas you need, you still need people with experience. No matter how much you wish for it, 25-year-olds don't have 20 years of experience. Older doesn't mean you aren't innovative. 

You make assumptions about age.

Baby Boomers are like this, and Millennials are like that. Or, we all better prepare for Gen Z, which is coming into the workforce now! 

First of all, when you think like this, you invariably leave out Gen X, who are currently between 41 and 56, and, second, while it's helpful to look at averages for general ideas, you can't make those assumptions about any single individual.

Each candidate and each employee is different, and they may or may not share the characteristics of their generations. Someone in their late 30s may be planning for retirement soon, while someone else in their 70s or older may be going strong. You may find a 50-year-old who wants to reinvent how business is done and a 22-year-old who complains about new software implementations because it's too hard to change.

Don't make any assumptions. Ask candidates the same questions regardless of their age. If you're looking for someone who can give a long-term commitment, make that clear in the job posting. 

An untapped market.

Age discrimination is real, which means there are quality candidates out there in their 50s or older. Think of the benefits you can gain by tapping candidates that your competitors ignore. 

Remember, older people can do jobs at all levels. Someone who had a career doing X may be looking to switch to Y. Sure, you can hire a new grad and train that person, but what about training someone else with years of experience in a different field? They may bring insights you couldn't get otherwise.

Remember: Age discrimination is illegal.

You shouldn't discriminate against older workers because it's morally wrong, but it's also illegal. Federal law protects everyone over 40. Some states protect everyone. It can be difficult for someone to prove age discrimination, but that doesn't make it right.

Asking people about retirement plans (unless they bring it up first), making comments about older people not being able to learn as quickly, or joking about their being over the hill may all seem appropriate at the moment. Still, they can be used in a lawsuit against you. 

Treat everyone fairly. Document reasons for discipline or termination and make sure you aren't treating people differently because of their age. It will benefit your business now and in the future.