Embodiments of the invention are concerned with a method and a system for scheduling the transmission of messages to a subscriber in a communications network on basis of communications events that are determined to have occurred from communications events generated by the communications network. The method includes identifying a communications event as one of a plurality of predetermined types of communications events on the basis of at least one said identified current or previous communications session, and, responsive to the identified communications event, triggering a scheduling process for scheduling transmission of a message to the subscriber, in which the scheduling process is dependent on the type of communications event.Thus in embodiments of the invention, the transmission of messages is determined on the basis of communications events associated with the subscriber; typical communications events include making calls, sending messages, switching off, switching on, roaming, cell to cell handover, answering calls, and trends relating thereto. The method can include reviewing call detail records so as to identify likely actions and availability of the subscriber, and using this information to ensure that messages are received by a subscriber at a time that is convenient to their actions and availability.