Because the plant geographer is essentially concerned with the spatial distribution of plants, the first step in analysing the basic information provided by collecting and recording is the preparation of plant distribution maps. These depict cartographically the recorded range of the plants in question and represent initial generalisations of the original information. On only very few maps is it possible to include every individual point at which a plant occurs, and therefore from the outset the plant geographer must exercise his judgement on the way he organises his material for cartographic purposes. Nearly all plant maps will involve the simplification and regrouping of the information to be shown, and carelessness at this stage will not only produce unhelpful and misleading maps but could also jeopardise the validity of theories put forward to explain the distributions concerned. Unfortunately, many plant geographers pay insufficient attention to fundamental cartographic principles, and published maps should be viewed as critically as their accompanying texts are read.