Complaint Letter about Your Colleague or Coworker

Dear [Manager Name],

Before I delve into the core purpose of my letter, I want you to know how proud and happy I am to be part of this wonderful team. It is always a pleasure to work together with professional people, all looking together at one common goal. But sometimes, one bad apple can ruin the experience for the rest. I'm usually very hesitated when it comes to complaints, but I'm writing this [letter/email] only after I've exhausted all other options. The bad apple I'm referring to is [bad employee name].

It is becoming increasingly difficult to cope with [his/her] continuous misbehavior and lack of conduct. I'm no longer able to focus on my work and I fear that this may affect my performance. I used to come to work with a cheerful spirit and unmatched enthusiasm, but now every work day is becoming a nightmare.

[Give examples here. What, when, and where it happened? Support your case with numbers, dates and facts.]

I kindly ask you to take immediate actions in order to fix this situation and restore things to their proper order. I have tried to contain and to adapt to the situation, but this is just too much to tolerate. I trust your judgment and I'm confident that you will find a fast and satisfying solution for all of us.

Thank you very much for your understanding.

Best Regards