2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/13167Our view of the properties of galaxies is strongly affected by the way in which we survey for them. I discuss some aspects of selection effects and methods to compensate for them. One result is an estimate of the surface brightness distribution. I believe this is progress, but considerable uncertainty remains.8 pages; invited review for IAU Colloquium 171, The Low Surface Brightness UniverseAstrophysicstext