The potential for pheromone-based mating disruption of the olive pyralid moth (OPM), Euzophera pinguis, in olive groves was investigated during the second flight period in small-plot trials in 2002. The female of this species emits a blend of (9Z,12E)-tetradecadien-1-ol and (9Z,12E)-tetradecadienyl acetate, which were synthesized for field tests. Mating disruption efficacy in 0.8-ha trials was evaluated using two parameters: reduction of male capture in pheromone traps and reduction of infestation in infestation-prone sites. White rubber septa containing 10 mg of pheromone blend as disruptant were applied at a density of 50 septa/ha for each treatment. Mean catches of E. pinguis males in pheromone traps were greatly reduced (> 95%) in pheromone-treated plots relative to similar traps placed in control plots. In addition, significant reductions were recorded (35-40%) in the oviposition and infestation levels during pheromone treatment. The total amount of pheromone blend released from disruption dispensers during the field trials was estimated to average 5.4 mg/ha/day, over 56 days.