The course presents the distribution patterns of plants on the Earth’s surface and the processes responsible for their development at different scales. In particular, the links between the distribution of floristic diversity and main climate factors are examined. Students will then learn - supported by examples taken by contemporary scientific literature - mainstream concepts and methods used to describe and investigate spatial-temporal relationships among genetic diversity, floristic diversity, geography and climate: presence/absence data, extent of occurrence, chorotypes, species dispersal and extinction, floristic provinces, regions, and kingdoms. Main data sources will be pointed out and practicals will be offered on how to elaborate the extent of occurrence and to assess its spatial-temporal evolution. To conclude, the role of phytogeographical researches will be discussed in the wider context of biodiversity conservation.