Customers make decisions about an organisation's service quality based on their experience with a multitude of other service organisations. When measuring customer service, businesses need to take into account how they compare with other organisations in their own industry and other sectors. Benchmarking is a useful tool for making this analysis. There are four main types of benchmarking to measure customer service: internal, competitive, non-competitive and best in class. This chapter provides an overview of different models and approaches that help organisations gain an objective view of their customer service effectiveness both in the private and public sector. The Excellence Model is best used when organisations wish to gain an objective measure of their business. The advantages of this method are that the assessment tool is comprehensive and encompasses employee as well as customer results. A measure of efficiency and effectiveness that many service organisations are beginning to adopt is 'Six Sigma'.