Introduction The W ARC-79 has allocated the band 22.5 to 23 G Hz in Regions 2 and J to the broadcasting-satellite service (BSS)@ part of which@ namely the band 22.55 to 23 GHz@ is shared with@ among others@ the inter-satellite service (ISS). On the basis of studies carried out in the USA and Japan this Report examines parametrically the orbital spacing required between space stations employing inter-satellite links and broadcasting satellites with respect to interference into the ISS link [CCIR@ 1978-82a and b] and interference into the BSS receiver [CCIR@ 1978-82c]. These analyses use new system characteristics from an example in Report 215 for high-definition TV using an RF bandwidth of 125 MHz. However@ an example for conventional TV is also given in Report 215. The analyses presented in this Report can also be applied to that case. Preliminary calculations done in the United States show that the high-definition case presented here would prove to be the more conservative. The parameters for the ISS assumed in the two analyses are given in ?? 2.1 and 3.1. As the definition of the ISS is in an early stage@ the parameters assumed in the two sections are different. Further study is required.