The same landscape can mean different things to different people, and a great deal of research into landscape is concerned with description, analysis and explanation of these differences. Meinig (1979) described ten versions of the same scene, through the eyes of different professions, but there are many more than ten versions, and profession is not the only factor in the differences. This chapter attempts to set out a framework for such studies of landscape perception and preference, and uses as a metaphor those types of spectacles used by opticians into which a variety of lenses can be inserted, when carrying out an eye inspection. The metaphor has its limitations; the intention of ‘correcting’ the vision implicit in the eye examination cannot be applied where the intention is merely to explain a preference. Also, some may see an implied presumption that landscape is only a visual phenomenon, whereas modern landscape research, and indeed landscape practice, is quite clear that landscapes are also apprehended through sound, smell, touch and even taste, a truth which will come as no surprise to landscape poets and novelists. Despite these faults, the metaphor remains a useful classification of much landscape research, also allowing the possibility (equivalent to the naked eye) for the work that presumes there to be some degree of perception and preference that is common to all humans – some universally accepted notions of landscape quality.