Professor Roy Maartens is the SKA Research Chair at the University of Western Cape. He is a cosmologist who analyzes the large-scale structure of the universe to extract information about the universe and to develop tests of Dark Energy and of Einstein’s General Relativity. MeerKAT and the SKA will allow Prof. Maartens and his fellow researchers to apply these ideas for the first time in the radio waveband. He was chair of the international SKA Cosmology Science Working Group (2013-2015) and a member of the SKA Science Review Panel (2014).