This paper describes the development and use of a piece of software, I
NTERACT, for analyzing situations under the control of several interes
ted parties. After briefly discussing forms of analysis used, it outli
nes the design philosophy of the software itself. Particular attention
is paid to its intended use in a decision support role. The functions
typically performed in the course of analysis are illustrated using a
worked example. Finally, avenues for further development are outlined
.