This report contains the results of the DTCS project (Spatial decision support for negotiation and conflict resolution of environmental and economic effects of transport
policies), financed by the European Commission, DG12-Unit D5, under contract ENV4-
CT96-0199. The project started in April 1996 and was completed in July 1998.
The DTCS methodology is based on spatial analysis and decision analysis. Spatial analysis
supports the search for the most suitable allocation of human activities (e.g., housing,
infrastructure) across space. This approach is used to analyse and predict spatial impacts
and to provide evidence on the consequences of spatial decisions. Spatial analysis includes
a powerful set of methods frequently implemented in Geographical Information Systems
(GIS). However, it still offers limited support to integrate in the analysis the views and
expectations of multiple decision actors. This last aspect is the focus of decision analysis.
It serves to explore the value systems of individuals involved in a decision, to support
problem structuring, to assess value judgement, to compare decision options and to
perform sensitivity analysis. The link between spatial analysis and decision analysis in DTCS is made through the concept of policy unit.