Earlier chapters of this report have reviewed present conditions and
trends in a number of socio-economic factors that are driving environmental
change. How these factors evolve will shape global and regional development
and the state of the environment far into the future. Trends may continue
as they have in the past or change speed and direction - perhaps even
going into reverse. Trends may lead to convergence or divergence between
circumstances in different regions of the world. Trends in one region
or responses to one driving force may oppose others that originate elsewhere,
or they may run up against absolute physical limits.
The scenarios explored in the pages that follow are based on certain
assumptions about how these driving forces will evolve and interact with
developing situations, potential future shocks and human choices. This
section briefly describes the assumptions made about driving forces underlying
the scenarios and, in particular, how these assumptions differ from scenario
to scenario. For descriptions of the scenarios see the next
The seven driving forces under consideration are demography, economic
development, human development, science and technology, governance, culture
and environment. The environment is included as a driving force because
it is more than a passive receptacle for change. Just as the assumptions
about human and societal behaviour shape the scenarios, so do the assumptions
about pressures exerted by the environment.
Developments arising from each of the driving forces will not unfold
in isolation from one another. Issues will interweave and chains of cause
and effect are likely to be hard to trace back to individual sources.
Finally, any number of possible future trends could be constructed from
the available array of variables. Narrowing down this range to a small
yet richly contrasting set of futures that are consistent, plausible,
recognizable and challenging, depends on starting out with an intelligent
set of assumptions.