Operational acceptance testing

This type of testing focuses on the operational readiness of the system to be supported, and/or to become part of the production environment.

[1] According to the International Software Testing Qualifications Board (ISTQB), OAT may include checking the backup/restore facilities, IT disaster recovery procedures, maintenance tasks and periodic check of security vulnerabilities.,[2] and whitepapers on ISO 29119 and Operational Acceptance by Anthony Woods,[3] and ISO 25000 and Operational Acceptance Testing by Dirk Dach et al., OAT generally includes:[4] During OAT changes may be made to environmental parameters which the application uses to run smoothly.

Typically OAT should occur after each main phase of the development life cycle: design, build, and functional testing.

In sequential projects it is often viewed as a final verification before a system is released; where in agile and iterative projects, a more frequent execution of OAT occurs providing stakeholders with assurance of continued stability of the system and its operating environment.

The primary emphasis of OAT should be on the operational stability, portability and reliability of the system.