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A letter of grievance is a letter by a consumer to a company or business complaining about its services. The letter may be about poor service, an over charge or a bad product. The purpose of your complaint letter is to inform the company about the quality of its service and suggest how it can be improved--not to vent your emotions. Most companies will be eager to fix a customer-service problem, and many will even compensate you for bad service.

Write the name and address of the recipient of your letter on the front, center of the envelope. If it's a large corporation and you don't know the name of who should receive the letter, address it to the company. Add "Attn: Human Resources" under the company name.

Write your return address in the upper, left corner. Be sure to place a stamp in the upper right corner.

Address the letter to the company or to the company's president or owner, if you know that person's name.

In your first paragraph, state the background. Describe your dealings with the company and state your grievance in general language. For example, if you're complaining to a restaurant, say something like, "I am writing to tell you about the quality of service during my recent visit to your establishment."

Describe the problem in the next paragraph, stating exactly what happened and how it affected you.

In the next paragraph, suggest how the problem can be solved. This is where you also request compensation or some other action you feel is appropriate.

Add a warning in the next paragraph if you think it is necessary to get results. Don't use aggressive language but state your demand clearly and emphatically.

Close the letter by politely stating your expectation that the company will reply to your complaint.

Fold the letter as you would any business letter, place it in the envelope and send it in the mail.