Soon after his unit reached the trenches in France, he planned a major raid near Fleurbaix, carefully preparing his men before launching it on the night of 1/2 July. This was a "silent" raid, being undertaken without a preparatory bombardment of the targeted German trenches. Wilder-Neligan split his 148 troops into three groups, and directed them to enter the German trenches about apart to avoid German enfilading fire. He trained his raiding party and conducted rehearsals in the days leading up to the operation. On the night of the raid, Wilder-Neligan used machine gun fire to cover the sound of his troops advancing across no man's land. When they were close, he called down a protective barrage behind the German trenches, with machine guns sweeping the enemy flanks. The raiders then rushed forward, entered the enemy trenches and engaging in heavy fighting. During the final rush, Wilder-Neligan came across a German observation post in advance of the enemy trenches. He killed two of the three enemy soldiers occupying it, but the third threw a hand grenade that wounded him severely in the shoulder and in the head, fracturing his skull. Despite his wounds, he continued to direct his men until they had all returned safely. During the raid, the Queenslanders killed 14 Germans, wounded 40, and captured 25 more along with a machine gun, for the loss of seven dead and 26 wounded. The Australian Official War Historian, Charles Bean, described this action as "perhaps the most brilliant raid that Australians undertook" at the time. The success of the operation was recognised by Wilder-Neligan's appointment as a Companion of the Distinguished Service Order, the second highest award for acts of gallantry by officers. The citation read: