Every great boss -- and every great entrepreneur -- hopes to have loyal employees. Yet loyalty has absolutely nothing to do with length of employment. Is a 20-year employee who does just enough to get by, criticizes you and your business at work and at home, and often undermines your decisions more loyal than a 1-year employee who genuinely embraces where you want to go, and works hard every day to help you and your company succeed?

While experience does matter, given a choice most bosses will take the "inexperienced" employee. Time of service matters, but performance matters way more.

So let's establish two levels of loyalty. The first level is employees who are loyal to your company. They work hard for their pay and are committed to the company's success. Loyal employees may someday leave, but while they work for you, they do their best and often even put the company's interests ahead of their own.

The second category, exceptionally loyal employees, hit the next level. They aren't just loyal to the company. They're also loyal to you -- even though their loyalty can be displayed in surprising ways.

Here's how you can tell if your employees are not just loyal to your company, they're loyal to you:

1. They are willing to tell you what you least want to hear.

As a general rule, the more rungs on the ladder that separate you and an employee, the less likely that employee will be to disagree with you. For example, your direct reports may sometimes take a different position or even tell you that you're wrong. Their direct reports are much less likely to state a position other than yours.

And entry-level employees will sing directly from the company songbook, at least when you're the audience.

Truly loyal employees know that you most need to hear what you least want to hear: that your ideas may not work, that your point of view is off, that you made a mistake.

They'll tell you because they know that, though you may not care much for what you hear, you care tremendously about doing what is best for your company and your employees.

2. They treat you not just like a boss, but also like a person.

Remember when you were in grade school and you ran into your teacher at, say, the grocery store? It was weird. She wasn't supposed to exist outside of school. You didn't see your teacher as someone who wore shorts and had friends and wore an AC/DC T-shirt and actually had a life.

Your teacher wasn't a person; she was a teacher.

Lots of employees see you that way, too--they don't see you as someone with dreams and hopes, insecurities and fears.

You're not a person; you're a boss.

Genuinely loyal employees flip the employer-employee relationship: They know you want to help them reach their professional and personal goals and that you want what's best for them--and they also want what's best for you, both at work and in your personal life.

They see you as more than just a boss, and they treat you that way.

3. They never criticize you in front of others.

"Bash the boss" is a game almost every employee plays, at least occasionally. (One of your employees is probably talking about you right now.) Partly they criticize you because it's a way of letting off steam, but mostly they do it because we all think, at least some of the time, that we can do a better job than the person we work for.

Criticism, mocking, sniping--when you're in charge, those things come with the territory.

They also chip away at the respect you work so hard to deserve.

Loyal employees get that. They don't gossip, they don't snipe, they don't talk behind your back--they give you the respect that they expect to receive, even when you're not around.

4. At the same time, they'll freely disagree (but they do it in private.)

Debate is healthy. Disagreement is healthy. Weighing the pros and cons of a decision, playing devil's advocate, sharing opinions--every leader wants to hear what his or her team thinks. It's not just enlightening; it's stimulating.

Truly loyal employees trust that they can share their opinions as freely as you do. In fact, they trust that you want them to--because you and the company benefit from an honest exchange of differing opinions and points of view.

But once a decision is made...

5. They support your decisions -- and, by extension, you -- in public.

I guarantee you've been in at least one meeting where someone says, "Look, I don't think this is the right thing to do, but I've been told we're going to do it anyway. So let's at least give it our best shot."

After that little speech, does anyone ever give it their best shot?

Even when they disagree with a decision, loyal employees don't try to prove you wrong.

They do everything they can to prove you right.

6. They tell you before they decide to leave.

I've never known any loyal employees who weren't also just good old-fashioned great employees. Because of that, you want them to stay. You need them to stay.

Still, sometimes they need to leave: For a better opportunity, a different lifestyle, to enter a new field, or to start their own business. But they also know their departure will create a tremendous hole, so they let you know what they're thinking to give you plenty of time to prepare.

Granted, if an employee is willing to tell you well ahead of time she plans to leave, or is just thinking about leaving, it means she trusts you to an exceptional degree. Clearly she knows you won't start to treat her differently or fire her on the spot.

She trusts you because she's been loyal to you. After all, she has put your interests ahead of hers a number of times -- and now she knows you'll do the same for her.

And if you won't, what kind of boss are you? The kind that doesn't deserve loyal employees.

Be the kind of boss that earns loyalty because you are loyal -- not in return, but first.