The Terrestrial Services Department (TSD) carries out technical and regulatory functions and provides assistance to administrations in the domain of international management of the RF spectrum, as specified in the Radio Regulations and various Regional Agreements, concerning terrestrial services (broadcasting, fixed, maritime mobile, aeronautical mobile, etc.).
It processes notifications of frequency assignments, maintains the Master Register and Plans concerning terrestrial services and publishes their updates at regular intervals.
It applies various administrative regulations dealing with allocation of international means of identifications (call sign series, MIDs) and with safety of life. To this end, it processes submissions for various service documents (List of coast stations, List of ship stations, etc.), publishes their updates and maintains their on-line versions.