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There is an increasing amount of international discussion on the standards which should be adopted for television broadcasting from satellites, and on th extent to which different transmissions can be accommodated within the limited frequency band which may be available. It is likely that a frequency modulation system will be employed, with the sound signal transmitted on a sub-carrier addedd to the vision signal. The report considers the most suitable amplitude for this sub-carrier, and describes subjective tests to provide data for establishing the acceptable level of interference between f.m. television transmissions occupying the same frequency channel. Although there as yet no plans for satellite broadcasting to the U.K., it is important for broadcasters to know the basic criteria, such as the protection ratios discussed in this report, for evolving suitable frequency assignments to different countries. The World Adminstrative Radio Conference on Space Telecommunications, June 1971, is expected to take only the first step by allocating a frequency band around 12 GHz, and possibly certain other bands, for television broadcasting from satellites. After the conference it will be desirable for discussions on detailed assignments for broadcasting services to take place quite soon, in order to ensure the most effective and equitable use of the band in the long term.