A sender-specified courtesy notification scheme to delay notification by a receiving device of the receipt of a data message is disclosed. A sender may specify a notification parameter defining a delay and send the parameter in association with the data message to a recipient. The recipient's receiving device evaluates the parameter and notifies in response. Local notification data defined by the recipient may also be evaluated. Received data messages subject to delayed notification may be hidden by the receiving device or quietly displayed (e.g. as per other received messages) until the expiry of the delay. Notification parameters and data can be formulated as one or more rules which may take into account the current location of the receiving device. A notification delay may be ignored in certain situations depending on recent use of the receiving device.