Our nation's greatest assets - our Soldiers - face a dynamic, competitive, and lethal operational environment (OE) that has evolved in recent years, one in which our adversaries will employ a mix of traditional, unconventional, and hybrid strategies. Our Army's physical readiness program must evolve to keep pace with the demands of modern war - our physical fitness test must evolve as well. Based on results of years of scientific study, the Secretary and Chief of Staff of the Army have directed replacement of the Army Physical Fitness Test (APFT). While the legacy APFT is an acceptable test for measuring general fitness, it does not adequately assess the domains of combat physical fitness. The six-event Army Combat Fitness Test (ACFT) was developed to better predict a Soldier's readiness for the demands of the modern battlefield. Like combat, the ACFT is both age and gender neutral. The desired end-states of ACFT implementation are an increase in physical readiness, a decrease in chronic injuries, and an evolution in the Army's fitness culture. This handbook is a compilation of products developed by the Center for Initial Military Training (CIMT) in preparation for the Army-wide implementation of the ACFT. The ACFT is in its initial stages and there will certainly be refinements as we receive feedback from the ACFT Field Test in Fiscal Year (FY) 2019. In the interim, this handbook provides commanders, leaders, and Soldiers with a single guide for preparing for and administering the ACFT in advance of Army-wide implementation in FY20.