With an ongoing mass loss the Antarctic Ice Sheet contributes to global-mean sea level rise at a rate of 0.4 mm/a. Thus, it plays a key role in global climate and provides a natural laboratory to study processes that interlink cryosphere, solid Earth, atmosphere and ocean. We discuss how GNSS and seismic networks in Antarctica were used to significantly advance our understanding of these processes, and how they should be maintained and extended to answer key science questions in the future.