This manual outlines the fundamental tactics, techniques, and procedures for infantry rifle platoons and squads in the United States Army. It details the operational doctrine for movement, formations, and actions on contact, serving as a foundational guide for soldiers and leaders.

As a United States Army Field Manual, FM 3-21.8 is an official publication intended for military personnel. Its content is authoritative within the context of U.S. Army doctrine for infantry operations at the platoon and squad level. The manual is designed to provide standardized training and operational guidance, ensuring a consistent approach to tactical execution.