This European Standard specifies requirements for the measurement of complaints and redress procedures related to the domestic and international postal service. It defines various types of complaints and for each of them establishes a methodology for measuring response rates for their acknowledgement, processing, and resolution by the service provider. It also specifies the requirements for the complaints management system to be set up by the service provider. This European Standard is applicable to all domestic and cross-border services within the universal service. It can be used for other postal services if appropriate.