Schmidt telescopes have, for some three decades, provided one of the most important sources of data for studies of the quasar population at all wavelengths. In the 1980s the combination of Schmidt telescope plate material and automated scanning machines such as COSMOS and APM allowed a new generation of projects to be undertaken, the results from which are largely responsible for our present understanding of the evolution of the optically–selected quasar population. The digitisation of photographic plates coupled with the computer–based selection of candidate quasars has meant that quantitative calculation of survey selection functions can be accomplished. The first results from surveys with such selection functions are beginning to appear, and progress is being made in constraining the form of the evolution of the quasar luminosity function at high–redshifts, a regime where there has been much disagreement over the nature of evolution. The (still) unique wide–field capability of Schmidt telescopes, coupled with the application of analysis techniques developed using the automated scanning machines, will ensure that Schmidt telescopes continue to make an important contribution to quasar–astronomy over the next ten years.