Writing a letter of complaint for services not rendered or inefficiency is a job that requires consideration and sensitivity. It is a formal letter, and needs to be formally addressed and formatted, leaving out personal grudges and emotional innuendo. Giving just the right touch, a combination of clarity, comprehensiveness and attention to detail are all important factors. It must not be made to appear like a personal or character attack. Professionalism is key.
Open the letter with a formal, businesslike greeting. Whether it is a letter from within the organisation complaining about the unprofessional behaviour of a fellow employee, or from outside the organisation complaining of the incompetence and lack of professionalism of the representative who irked you, it is important to set the right tone from the start. Address the head of the company and introduce yourself and the reason you are writing in the beginning of your letter. Do not expect the reader to search the letter for the reason -- it should be stated clearly at the start.
Provide details in the form of a clear, chronological narrative (dates, episode, results) and proof (receipts, product, bills) that give your complaint authenticity. Use specific details from the incident to give a clear and coherent account of what happened and why it is cause enough for you to write the letter. Keep your tone as objective as possible while providing all the necessary information.
Continue with the main body of the letter. Give justifiable reasons why there is the need for the complaint against the employee. The original point stated in the opening must be elaborated and supported with proof.
Close the letter confidently and politely by adding the closing part of the salutation. After writing "Sincerely," leave four lines for your signature and underneath add personal details such as name, telephone number and address.