Table 2.

Invasion ecology is confronted with three domains of difficulties. Domain B: Difficulties caused by the peculiarity of the invasion process, and consequences for the scientific approach of invasion ecology; letters and numbers in parentheses refer to Table 3

	Difficulty	Consequences for the scientific approach
B1	Complexity: many different factors interact in determining invasion success	Synthesis needed to integrate the interacting influence of multiple factors (C2)
B2	Context dependence: invader success varies in time and space	Historic data are relevant (C4) Case studies needed, but also synthesis (C2)
B3	Cultural influences at each stage of the process	Socio-cultural sciences have to be integrated for explanation and prediction (C8)