During agonistic contests between size-matched Cambarus robustus crayfish males of breeding form, the eventual winners and losers initiated approximately the same number of fights. However, winners and losers differed in the frequencies and types of initiation behaviours used. The losers used almost exclusively the more subtle Ambivalent Contact initiation behaviours, whereas the winners used primarily the aggressive Lunge and Claws Raised initiation behaviours. The eventual losers initiated the vast majority (81.5%) of the very first fights in the overall agonistic contests. The type of initiation behaviours used by these crayfish from the beginning of the agonistic contests allows us to predict the eventual status (dominant or subordinate) of each of the two combatants. Furthermore, the frequency of the Lunge initiation behaviours used by the winners is significantly and negatively correlated with the total time spent fighting. As the dominant-subordinate relationship between the two combatants of each pair becomes established, there is a reduction in both the number and the duration of fights.