Apology letter for client should follow a pattern of every usual business correspondence. Whether is related to mistake you have done, wrongful shipment or irregularities with business operations it should contains the following elements: The client is angry, so you should apologize. Good relationship should be maintained, especially when you are dealing with regular client on several projects. So you should introduce the topic (the issue) in the first paragraph of the apology letter for client. The next paragraph should emphasize the responsibilities of the client, and your company. It is essential to describe all the details so the client would know what your responsibility was and whether something was his fault or the company you are employed at.Customer relations management is one the most important practices in the modern companies.