By: AllBusiness.com

You might think it's fairly obvious that certain sentiments should never be included in a letter of resignation. But you might be surprised at what some people think is acceptable to include in this final communication between employer and employee. Insulting the boss, blaming colleagues, becoming overly emotional, offering unnecessary information, omitting key information (your last day, for instance) are all examples of what should be avoided when writing a formal resignation letter.

Be sure you craft a well-written resignation letter by first taking the time to gather your thoughts, maintaining a professional and positive tone throughout, and proofreading your letter carefully. To see a sample letter, check out How to Write a Professional Resignation Letter.

Remember, too, that even though you are preparing to depart a place you may not be saying farewell to the people you have come to know -- another reason to leave on a professional note. Behaving in any other way could jeopardize the relationships you've formed during your time there, as well as future opportunities you may not be aware of yet.

Here are 10 things you should not include in your letter of resignation:

1. I've hated every minute here. You may sincerely want to say this and it might even be true, but that's something you can keep to yourself and your close friends.
2. You are the worst boss I've ever had. Again, it might be true, but a resignation letter should never become so personal.
3. Why wasn't I treated more fairly? You're not likely to get an answer to this type of question. In addition, if you claim you weren't treated fairly and you're now leaving, the company may assume that you've hired a lawyer. This isn't the place to raise issues like this.
4. One day I will make this right. Do not, under any circumstances, include threatening language in your letter. Remember, once something is in writing it might as well be filed under "forever." No one likes to be threatened, especially in writing. And it can have serious legal ramifications for you down the road.
5. In my next job, I will have very important duties, etc. Your employer doesn't need to know this and probably doesn't care too much either. It's a resignation letter, not an announcement of your future plans. Of course, if your supervisor asks where you're going, you are free to provide that information. But if you're headed to a competitor, you might not want to be specific.
6. Please let me know if another position becomes available. Why on earth would an employer consider you for another job at the company as you walk out the door? Be smart in your resignation letter.
7. Here's the problem with this organization. Like the other 101 suggestions you have for improving the company, pointing out areas for improvement at this stage is not only inappropriate, but irrelevant. It's a resignation letter, not your opportunity to lecture.
8. Mary Smith sabotaged my work. Even if Mary Smith did sabotage your work, naming names in a resignation letter will get you nowhere. It's unprofessional, ill timed, and not the appropriate forum.
9. I will miss my team more than you can imagine. It's OK to express your feelings, but you must temper those emotions when you put your thoughts on paper.
10. You are going to miss me. You may not exactly want to put it that way, but it's tempting to want to remind people of your contributions. However, this is not the place to toot your own horn.

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