This document is applicable to IT services that support the needs of an individual user or a business. IT services can be delivered personally or remotely by people, or by an IT application that could be in a local or remote location (see AnnexA). These include two types of IT services: services completely automated provided by an IT system; services provided by a human using an IT system. This document describes the use of two quality models for IT services. This document defines an IT service quality model composed of eight characteristics (which are further subdivided into sub-characteristics) that relate to properties of the IT service made up from a combination of elements including people, processes, technology, facilities and information. This document describes how the quality in use model in ISO/IEC25010 which is composed of five characteristics (some of them are further subdivided into sub-characteristics) can be applied to the outcome when an IT service is used in a particular context of use. This model is applicable to the complete service provision system composed of people, processes, technology, facilities and information. The characteristics and sub-characteristics provide consistent terminologies and check lists for specifying, measuring and evaluating IT service quality. The use of the IT service quality models can help: IT service providers to identify service quality requirements, and evaluate and improve the quality of the service provided; customers to specify their requirements for the quality of service, define the acceptance criteria for service, and evaluate the quality of an IT service; and a third party to evaluate the quality of an IT service.