The structure of a system ofNvariables is defined to be the set ofNdependency relationships giving, for each variable, the set of other variables upon which it is statistically dependent. Because statistical dependence is indicated by the transmission measure of information theory, this set can be found by finding the smallest subset of variables for whichT(subset : variable) is a maximum. Sampling considerations of this method are discussed, and the results of 21 experiments with it are given. The results are compatible with those of other structural modelling methods.