An analysis of a pheromone trapping system was performed to study the possibility of theoretically estimating the efficiency of a boll weevil pheromone field trapping system. Release-capture data for a single trap were used to establish percent capture versus distance from the trap. A computer simulation model predicting trapping efficiency showed that results are very sensitive to the responsiveness characteristics of the population. Theoretical results also showed sensitivity to trap spacing and identified some specific research needs.