The availability of a large and diverse collection of stored modules s
uch as data relations and decision models is a desirable feature in a
decision support system (DSS). However, it is usually infeasible to de
sign a DSS in which every problem instance can be solved using a singl
e module. Instead, it may be necessary to combine several stored modul
es into an integrated model that is sufficient to solve the given prob
lem. We show that modules such as data files and decision models in a
DSS can be usefully represented by a metagraph, a graph-theoretic cons
truct that captures relationships between pairs of sets of elements. I
n addition to the visualization benefits that graphical representation
offers, we show that many useful questions faced by the designers and
users of DSS can be addressed by exploiting analytical properties of
metagraphs. In particular, we show that the process of model integrati
on can be significantly facilitated by exploiting certain connectivity
properties in metagraphs.