This article describes the field administration facilities of the Duplex Multiple Environment Real Time (DMERT) operating system, as provided on the 3B20D Processor. These facilities are: Recent Change/Verify, the subsystem that allows manipulation of office‐dependent configuration information; Field Update, the software change mechanism; and System Update, the component used to install a new generic program in an office. The article also includes information on how these capabilities fit into the overall scheme of field support in an in‐service office environment.