Emergency telecommunications service (ETS) is a national service providing priority telecommunications to the ETS authorized users in times of disaster and emergencies. This Supplement identifies completed and ongoing work related to emergency telecommunications service (ETS) occurring in various ITU-T study groups, as well as the status of this work. This roadmap captures the results from an analysis of existing work activities related to the development of ETS capabilities for authorized users. Specifically, it identifies the study tasks that have been added to the work plans of individual Questions of the relevant study groups and their status. It captures identified gaps that exist, as well as the plans which show how these gaps will be addressed. National standards support the origination and termination of ETS calls in national networks. (This Supplement recognizes that ETS calls may include ETS voice, video and data calls originating or terminating in: the PSTN, wireless networks, and NGN networks.) These national standards complement the ETS-related ITU-T Recommendations, which are intended to support the extension of national ETS calls across international boundaries. It is understood that ITU-T Recommendations must address situations where invocation of ETS is restricted to users authorized by their respective governments and, where international agreements are needed to honor authorization in the originating network when delivering the call in a destination network which is a national network different from the network in which the invocation of the service occurred. Provision has been made to capture relevant ETS-related national standards and other SDO ETS-related standards as well, in this Supplement. However, as these other SDO developed and developing standards are not ITU-T's responsibility, ITU-T takes no position with regards to their integrity or completeness. This Supplement may identify the dependencies of ITU-T ETS work on activities that are, or which should be, underway in other external standards development organizations. Individual-to-authority communications are outside the scope of this Supplement, e.g., calls from the general public using national, regional or local emergency and public safety services to seek assistance. Activities related to the support of emergency telecommunications, which are not explicitly related to ETS, are outside the scope of this Supplement.