Species introduced to new regions through human activities 
are termed alien species. Invasive alien species represent 
a subset of alien species, being animals, plants and other 
organisms known to have established and spread with 
negative impacts on biodiversity, local ecosystems and 
species. Many invasive alien species also have impacts 
on nature's contributions to people (embodying different 
concepts such as ecosystem goods and services and 
nature's gifts) and good quality of life.4
 Some of the most 
problematic invasive alien species arrive through multiple 
introduction pathways and repeated introduction.
THE THEMATIC ASSESSMENT REPORT ON INVASIVE ALIEN SPECIES AND THEIR CONTRO
The thematic assessment report on
INVASIVE ALIEN SPECIES
AND THEIR CONTROL
DEFINITIONS, CONCEPTS
AND THE CONTEXT OF 
THE ASSESSMENT