A method performed by a computer system (100, 120), said method comprising: providing a rules storage that provides one or more rules to determine non-productive wireless device (103A to 103N) usage at a site; using a software agent running on a wireless device (103A to 103N) to determine a user logged into the wireless device (103A to 103N) used at the site; using a wireless communications sensor system to determine use of wireless devices (103A to 103N) at the site, wherein using the wireless communications sensor system includes using the wireless communications sensor system to determine a device identity of the wireless device (103A to 103N), a location of use of the wireless device (103A to 103N) at the site using trilateration and a duration of usage of the wireless device (103A to 103N) used at the site; and using the one or more rules to determine whether the determined use of a wireless device (103A to 103N) is non-productive, wherein using the one or more rules comprises: - determining, using the device identity of the wireless device (103A to 103N), whether the wireless device (103A to 103N) is either a company owned device or an unauthorized device, and flagging the wireless device (103A to 103N) as non-productive if the wireless device is unauthorized; - if the wireless device (103A to 103N) is a company owned device, verifying whether the user exists by checking against an authentication server, and flagging the wireless device as non-productive if the user does not exist; - if the user exists, determining whether the wireless device (103A to 103N) is allowed in the location of use, and flagging the wireless device (103A to 103N) as non-productive if the wireless device (103A to 103N) is not allowed in the location of use; and - if the wireless device (103A to 103N) is allowed, checking whether the user is using the wireless device (103A to 103N) for longer than an administrator defined threshold, and flagging the wireless device (103A to 103N) as non-productive if the wireless device (103A to 103N) exceeds the threshold, otherwise flagging the wireless device as productive. providing a rules storage that provides one or more rules to determine non-productive wireless device (103A to 103N) usage at a site; using a software agent running on a wireless device (103A to 103N) to determine a user logged into the wireless device (103A to 103N) used at the site; using a wireless communications sensor system to determine use of wireless devices (103A to 103N) at the site, wherein using the wireless communications sensor system includes using the wireless communications sensor system to determine a device identity of the wireless device (103A to 103N), a location of use of the wireless device (103A to 103N) at the site using trilateration and a duration of usage of the wireless device (103A to 103N) used at the site; and using the one or more rules to determine whether the determined use of a wireless device (103A to 103N) is non-productive, wherein using the one or more rules comprises: - determining, using the device identity of the wireless device (103A to 103N), whether the wireless device (103A to 103N) is either a company owned device or an unauthorized device, and flagging the wireless device (103A to 103N) as non-productive if the wireless device is unauthorized; - if the wireless device (103A to 103N) is a company owned device, verifying whether the user exists by checking against an authentication server, and flagging the wireless device as non-productive if the user does not exist; - if the user exists, determining whether the wireless device (103A to 103N) is allowed in the location of use, and flagging the wireless device (103A to 103N) as non-productive if the wireless device (103A to 103N) is not allowed in the location of use; and - if the wireless device (103A to 103N) is allowed, checking whether the user is using the wireless device (103A to 103N) for longer than an administrator defined threshold, and flagging the wireless device (103A to 103N) as non-productive if the wireless device (103A to 103N) exceeds the threshold, otherwise flagging the wireless device as productive. - determining, using the device identity of the wireless device (103A to 103N), whether the wireless device (103A to 103N) is either a company owned device or an unauthorized device, and flagging the wireless device (103A to 103N) as non-productive if the wireless device is unauthorized; - if the wireless device (103A to 103N) is a company owned device, verifying whether the user exists by checking against an authentication server, and flagging the wireless device as non-productive if the user does not exist; - if the user exists, determining whether the wireless device (103A to 103N) is allowed in the location of use, and flagging the wireless device (103A to 103N) as non-productive if the wireless device (103A to 103N) is not allowed in the location of use; and - if the wireless device (103A to 103N) is allowed, checking whether the user is using the wireless device (103A to 103N) for longer than an administrator defined threshold, and flagging the wireless device (103A to 103N) as non-productive if the wireless device (103A to 103N) exceeds the threshold, otherwise flagging the wireless device as productive.