This paper presents an analysis of a major wilderness preservation controve
rsy concerning the Tatshenshini-Alsek area in north-western British Columbi
a. it demonstrates how structured judgements about fundamental objectives,
potential impacts, and key trade-offs can be used to gain insight into a co
mplex policy decision, even when detailed information is scarce. The basic
steps of a decision analysis are employed, including structuring objectives
and measures, developing alternatives and characterizing uncertainties reg
arding impacts. A workshop involving nine senior provincial government expe
rts in relevant areas was held to investigate the range of views about trad
e-offs involved in the decision. A constructive, small group elicitation ap
proach was used to characterize value trade-offs that were summarized in te
rms of value function, which was then used to evaluate the alternatives. Th
e study provided information for the provincial government decision to turn
the whole area into a park, foregoing mining development. (C) 1999 Academi
c Press.