Pheromone gland extracts of grape berry moth females, Endopiza viteana Clemens, contain the main pheromone component, Z9–12Ac, at ≈1.2 ng per female, together with both geometric isomers of 11–14Ac, and a number of saturated acetates and alcohols of the chain length 12–16. The analogous alcohol, Z9–12OH, was found in some gland extracts. Trap capture of males was significantly increased by adding 0.5 or 2 μg of Z11–14Ac to 10 μg of the main compound, Z9–12Ac; whereas, adding 0.5 or 2 μg of E11–14Ac had no significant effect. In contrast, the addition of 5% Z9–12OH to the main compound resulted in a strong reduction in trap capture. Traps baited with a blend of Z9–12Ac and its geomeric isomer, E9–12Ac, which was not detected in gland extracts, were significantly less attractive than traps baited with blends of Z9–12Ac and Z11–14Ac. Knowledge of pheromone components and antagonists is essential for development of the mating disruption technique. The compounds identified in E. viteana are behaviorally active in the three most important tortricid pests of grape, Vitis vinifera (L.), in Europe. It may thus be possible to use a single blend of synthetic pheromone for control of several species.