It is the objective of this contribution to clarify the
core ideas behind the concepts of the VE and to
structure the mainstream of VE developments. In the next
section we will give a short definition of the VE. Then
we will characterize the concept of the VE. In the
consecutive chapters we will discuss when to move to VE
and which management challenges need to be addressed for
its successful implementation. We will conclude with a
short outlook on future developments. pdf
