Abstract: In a data processing and transmission digital network wherein users have been individually assigned a virtual machine including a memory zone and a capability for sharing hardware and software facilities for entering processing and mailing data to one another using terminal keyboards attached to the network, a mail follow-up system is provided for monitoring and processing selected mail items. The system includes a facility for generating mail tags including predefined fields; a facility for tracking the mail and deriving therefrom mail characteristic data; a facility for storing said characteristic data into tag fields; a facility for storing the filled-in tags into a file and for accessing and processing predefined mail fields, whereby processed tags are automatically transferred to different tag files. The system further includes an administrator system for centrally administrating the tagged mail on a departmental basis.