Method validation is an essential part of establishing and ensuring the quality of analytical data. It cannot be guaranteed that data will be fit for purpose unless the performance of the test method has been studied and demonstrated to be adequate. Method validation is the process that provides evidence that a test method is capable of providing data that are suitable for a particular application. It is a requirement of the ISO/IEC 17025 laboratory accreditation standard and many other sectoral regulations and directives. Method validation should always be a planned activity. This course introduces the statistics required for interpreting validation data and provides the tools to plan and carry out effective validation studies.