In warfare, infiltration tactics involve small, lightly equipped infantry forces attacking enemy rear areas while bypassing enemy front line strongpoints and isolating them for attack by follow-up troops with heavier weapons.

These tactics emerged gradually during the later years of World War I, used in various forms by the Russian general Aleksei Brusilov in Brusilov Offensive of 1916, by the Canadian Corps at the Battle of Vimy Ridge in April 1917, and by the Germany military in the Siege of Riga in September 1917 and the Battle of Caporetto in October 1917.

The tactics became especially associated with the stormtroopers of the German Army, and were also called Hutier tactics, after General Oskar von Hutier, who used these tactics to great effect during Operation Michael in March 1918.

Infiltration tactics were first proposed in the Allied armies by French Army captain Andre Laffargue. Laffargue published a pamphlet "The attack in trench warfare" in 1915, based upon his experiences in combat that same year. He advocated that the first wave of an attack identify hard-to-defeat defenses but not attack them; subsequent waves would do this.