B. S. Sathyaprakash is the Bert Elsbach Professor of Physics at Penn State. His research in gravitational waves began in the late 1980s when he designed the matched-filter search for binary black holes and neutron stars that is stillused in the analysis of LIGO and Virgo data. His research resolves around black holes, neutron stars, cosmology, and large-scale structure of the Universe. He also carried out strong field tests of general relativity. He is currently leading the worldwide effort to develop the science case for the next-generation gravitational-wave observatories such as the European Einstein Telescope and the US Cosmic Explorer.