Abstract: To set a night service configuration, a configuration control (KS) in the private branch communications exchange (NK) is activated from an internal or external handset or a switchboard position by dialing a call number. A sequence of numbers then entered is interpreted as an authorization code. The subscriber group for which incoming calls are to be diverted is selected by a sequence of numbers subsequently entered. A further sequence of dialed numbers determines the target handset or the target switchboard position for receiving the diverted calls. The configuration control (KS) then forms an administration and maintenance order, which is transmitted to the operating system of the private branch communications exchange.