The CCSDS has, with the participation of most of the world's major space agencies, established a number of important recommendations for space data system standards. The activities cover (1) radiometric, i.e. tracking and flight dynamics data, (2) standard format data units for data transfer, archiving and retrieval and (3) data structures and operation procedures for telemetry, command, timing and radio frequency systems. The paper covers the progress of work in this last group of topics and in particular, the acceptance and application of the recommendations in the planning of the infrastructure and projects of the CCSDS participating agencies. One outstanding example in this context is the US Space Station with Canadian, European and Japanese participation, all four also supporting CCSDS activities. For this project, the CCSDS is making special effort by providing intensive consultancy for the designers of the data systems. Other examples of a positive reaction on the endeavours to promote worldwide standardisation of space data systems will be addressed.