The operating microscope has transformed the surgery of glaucoma from a hit and miss affair to a very precise art. This is not to say that adult glaucoma surgery cannot be undertaken without sophisticated aids. Of course, it can, but as our understanding of the underlying mechanisms of the glaucoma improves, so do the methods of dealing with it. These techniques require more and more precise surgery which can only be achieved with the aid of high magnification and perhaps more important, finer and more delicate instrumentation.