Introduction This Report describes how mobile-satellite service (MSS) systems can provide disaster relief radiocommunications. In addition@ it provides descriptions of the operating and planned MSS systems which can provide such operations. The wide coverage area of an MSS system is particularly helpful as the location and time of occurrence of a disaster event is unpredictable and as an MSS system operation is typically independent of local telecommunications infrastructure which may be lost by the disaster event@ and given that MSS systems have wide-area earth coverage@ they can provide for disaster relief telecommunications. Furthermore@ most mobile earth stations (MESs) are battery powered and so can operate for some period of time even if the local electricity supply is non-functioning and moreover some MESs also come with solar and/or wind chargers. Since MSS systems do provide very large coverage areas@ spectrum coordination is accomplished on a regional or global basis. Each system is constrained to operate on frequencies authorized by Administrations as identified in Recommendation ITU-R M.1854.