red Rasio's research spans a wide range of topics in theoretical astrophysics, including: exoplanets and planet formation; the dynamics of dense stellar systems (globular clusters, galactic nuclei, young star clusters); hydrodynamic stellar interactions (stellar collisions and mergers, binary coalescence, common envelope evolution); and relativistic astrophysics (neutron stars and black holes, gravitational waves, relativistic star clusters, radio pulsars). His most recent work has focused on the dynamics of extrasolar planetary systems, gravitational wave sources for laser-interferometer detectors (LIGO, LISA), and the formation of massive black holes through stellar dynamical processes.