My research is centred around large surveys, primarily of extra-galctic objects but also of Galactic sources, carried out using large optical telescopes on the ground or in space. In particular, we have made spectroscopic surveys of dwarf (i.e. low luminosity) galaxies in the nearby clusters Virgo and Fornax, the highlight of which has been the discovery of an entirely new class of stellar systems, which we call Ultra-Compact Dwarfs or UCDs. I am also a member of the international teams carrying out the Hubble Space Telescope Treasury Survey of the Coma Cluster, the GAMA (Galaxy and Mass Accumulation) survey and the infra-red Herschel-ATLAS survey. Nearer to home, I am a member of collaborations carrying out surveys of the plane of our own Galaxy in the hydrogen alpha emission line.