Ten things never to put in email (or writing):

1. Any message or sentiment you would not be happy to have blown up to 100 times its original size and projected on the conference room wall with your company's executive team in the room. Or published in the Washington Post.

2. Your job-search plans, target employer list, headhunter contact details, job search correspondence, and other information about your not-yet disclosed job search.

3. Discussion of illegal activities (including the office football pool).

4. Threats, even joking, toward any person, organization, or group.

5. Confidential or proprietary company information that you do not have permission to share. Don't even discuss this with your boss ... if it gets forwarded, it still has your name on it.

6. Gossip.

7. Your frustration with your manager, another manager, or the company in general. If you don't like a policy, plan, or decision, you can argue to change it, but keep it professional and polite and share it with the person who can influence the outcome ... not people who can't.

8. Your romantic or amorous thoughts about anyone ... whether they work with you or not.

9. Jokes or humorous stories that are risque or derogatory toward any group of people. Corny "Dad jokes" and self-denigrating jokes are usually safe.

10. Criticism, even in jest, of a colleague, vendor, customer, partner, job applicant, consultant, or government representative. If you have mean thoughts about someone you work with, tell somebody who doesn't work there. Verbally.