Ecology of invasion of animals and plants was established as a science of invasion ecology in the beginning of the second half of the 20th century. Rapid development of the field of ecology have been evident since the end of the last century and following decades of the 21st century. The paper deals with current development of the ecology discipline, including critiques of invasion terminology, diversity of hypotheses and concepts, as well as xenophoby appeared related to aliens as invaders. Invasion biology have been an attempt to integrate alien animals and plants reseach into one science. In last decade new science of invasions is developed, characterized by multiand interdisicplinarity, supported by social and economy sciences. Numerous frameworks have been developed in an attempt to unify different concepts and definitions, facilitate generalisations, and to improve the link between science, policy, and management.