A reader writes:

My husband is a wonderful dentist, but has not been exactly the best manager. He has a small office with one employee who has been there for 27 years. When she started 27 years ago he sent her a general confirmation letter that stated her salary at the time and time off. The rest was pretty general.

I am a computer consultant who came in to update his office. What I have found has been unbelievable - to both me and my husband. The books were off by $9,000, recalls weren't being made, etc. On top of that, she can't even understand the fundamentals of computers so she can't do many elementary aspects of her job.

She has blatantly ignored instructions I have given her, she has lied, and more.

She is good with patients. That is her redeeming quality.

I think we should fire her. I have documented everything. After the last conversation, I wrote everything down and asked her to sign or to write her version that we could staple to the appraisal. She refused to sign and did not write up anything.

My husband is concerned that she will try a lawsuit since she has worked there so many years. I say she doesn't have a ground to stand on.

I know people can collect unemployment if they are incompetent. How about if they have lied or if they have just ignored instructions?

Since we sent her the initial employment letter - is she still considered at will or is she under contract?

Your husband is worried that she will file a lawsuit based on what? You're allowed to fire people for being incompetent, or for pretty much any other reason you want, as long as that reason isn't discrimination based on a legally protected category (race, religion, sex, disability, etc.). That's not to say that some people don't file frivolous lawsuits, but there's nothing you can do about that, and you certainly can't be held hostage to a bad employee by fear of that.

Now, normally I would advise you to see if you can figure out why this woman's performance is so bad. Does she need additional training? Better guidance on priorities? Some other sort of help? Plenty of struggling employees can be turned around. However, in this case, it sounds like there are deeper problems, particularly in light of the lying and the refusing to sign the appraisal (which indicates she's deeply out of alignment with you and not doing anything constructive about it, at least not from what I can see here).

Frankly, if she's lying about things, that's grounds for firing without a warning. But this woman has worked for you for 27 years, so I recommend proceeding a bit more deliberately that that.

Sit her down and say something like, We've had some recent conversations about some serious performance concerns, and I haven't seen the improvement that we discussed. I need to let you know that these issues are now at the point where your job is in jeopardy. We will need to replace you if these issues aren't immediately corrected.

Be explicit about the fact that she's in danger of being fired; too often managers mess this step up because it's hard to tell someone their job is in danger. Believe me, it is much kinder to say it explicitly than to give no warning. Tell her explicitly: Your job is in jeopardy. We need to see immediate improvement or we will need to replace you. Do not hint around; come out and say it.

While you're not required to explicitly warn someone before firing them, this post explains why it's a good idea.

From there, you don't need a long, drawn-out probationary period; if there's going to be improvement, you're going to see it quickly. Keep a close eye on her, and if you're still seeing serious issues a week or two later, then it's time to take action. Read this post for specific advice on how to conduct the firing.

Regarding unemployment, she'll likely be eligible for it. To prove her ineligible, you'd have to show deliberate misconduct, which you probably can't do here. (But also, why fight her on unemployment? You're firing her; showing some compassion in this area is not just kind, but also smart -- angry ex-employees denied unemployment are more likely to harass you with frivolous lawsuits.)

Regarding the initial employment letter 27 years ago, it sounds like a pretty standard at-will offer of employment. Unless she's signed a contract with you somewhere along the way, or unless you have an employee handbook that says employees are anything but at-will, she should indeed be an at-will employee, meaning that you or she can terminate the relationship at any time.