An effective complaint handling system is an extremely important part of any quality system. Manufacturers should understand that any complaint received on a product shall be evaluated and, if necessary, thoroughly investigated and analyzed, and corrective action shall be taken. The results of this evaluation should lead to a conclusion regarding whether the complaint was valid, what the root cause of the complaint was, and what action is necessary to prevent further occurrences. Complaints cannot be ignored. They are an excellent indicator of problems with the use, design, and/or manufacture of a product. A single complaint that is thoroughly investigated may lead a company to take remedial or corrective action. It may also take an ongoing analysis of numerous complaints before a trend is spotted that causes a company to initiate changes in their product, labeling, packaging or distribution.