Elaine Sadler has carried out world-leading research in the fields of astrophysics and galaxy evolution. Her fundamental contributions include the discovery that most bright elliptical galaxies have a weak central radio source powered by black-hole accretion, and the first measurement of the cosmic evolution of low-power radio galaxies over the past 5-6 billion years. By identifying the optical counterpart of the gamma-ray burst GRB 980425 as a supernova in which the core collapsed to a black hole rather than a neutron star, Professor Sadler has also made a ground-breaking contribution to the field of high-energy astrophysics.