EN
Among many threats to global biodiversity, invasion by alien species are perceived as very important. Activities aimed at counteracting this process should be preceded by updating the list of alien species and choosing appropriate terminology and classifications. In the paper, terminology still used by Polish authors is compared with that used in current English-language publications. Some examples are given to support the thesis that particular alien species should be periodically reviewed with respect to distinguished groups of synanthropic plants. The need for review can be supported by many examples of species classified only two decades ago as ephemeral and currently belonging to established elements of the local floras of some regions. Introduction of the EU Strategy on Invasive Alien Species will require compiling different lists of alien plants according to their impact on the environment, the economy or health. Papers published recently in Poland will help elaborate so-called white, black and gray lists of alien plants, but some activities aimed at implementing monitoring of invasive species should be undertaken, as should the elaboration of legal solutions.