A common reply to a complaint letter can be divided into five parts: acknowledgement of receipt, Investigations made and results, apology or regret, explanation and solution.

Upon receiving a letter of complaints, you must acknowledge your receipt by answering it promptly. You should then carry out an investigation immediately to look into the matter and gather detailed data, which will help you make a sound judgment. If the complaints are justified, an apology should be made and an explanation be given. And at the same time you should propose a solution by either offering compensation or putting forward a compromise. If the complaints are unjustified, the responsibility for the problem leading to the complaints can be rejected and the reasons should be given as well. The following can best illustrate the process.