• those where complaints are reviewed by a separate department (or individual); or
• those where complaints are reviewed by several levels of progressively senior staff.

The nature of the complaint should be the most important consideration in determining your point-of-entry in the internal complaint mechanism (ICM). It may be more efficient and effective to have less complex complaints heard and dealt with where they originate, while more complex decisions may require review by a senior manager or committee that is removed from the original decision. Resources can be a significant determining factor in the model you choose.

An issue often related to the complexity of the decision is the need, or perceived need, for an "independent" reviewer. One of the most significant factors that leads complainants to contact external agencies or the media is the feeling that they did not or could not get a fair review of their complaint. An ICM must be credible to complainants, who often feel they will not get a fair review if the complaint is reviewed where the alleged error originated. Having a separate complaint-handler or department may address concerns of this kind. It is important, however, not to describe your complaint-handler as "independent" unless such independence exists.