In July 2001, the Space Domain Task Force of the Object Management Group (OMG) issued a Request for Proposal (RFP) on Telemetric and Command Data Specification. This RFP solicited proposals that define telemetry and commanding data specifications in support of all phases of the satellite, payload, and ground segment lifecycle: system design, development, test, validation, and mission operations. In fact, telemetry and commanding data design is still often performed multiple times in multiple formats by multiple contractors during the lifecycle of the satellite, well before the satellite is ever deployed for mission operations. Standardisation of telemetry and commanding data descriptions for spacecraft health and safety monitoring, as well as payload interfaces, will reduce the cost of these implementations and decrease the development schedule, integration, and test of the satellite and its component systems. A common, adaptable specification can also be used to support multiple heterogeneous missions, facilitating interoperability among ground control systems, simulators, testing facilities, etc.