This manual, Army Techniques Publication ATP 4-33 Maintenance Operations July 2019, describes operational Army maintenance operations and focuses on the conduct of maintenance operations at the operational and tactical-level. Its primary focus is on maintenance organizations and their missions, but also addresses the roles and functions of strategic level maintenance organizations that provide logistics and individual Soldier support services. The principal audience for ATP 4-33 is all members of the profession of arms. Commanders and staffs of Army headquarters serving as joint task force or multinational headquarters should also refer to applicable joint or multinational doctrine concerning the range of military operations and joint or multinational forces. Trainers and educators throughout the Army will also use this publication. ATP 4-33 uses joint terms where applicable. Selected joint and Army terms and definitions appear in both the glossary and the text. Terms for which ATP 4-33 is the proponent publication (the authority) are italicized in the text and are marked with an asterisk (*) in the glossary. Terms and definitions for which ATP 4-33 is the proponent publication are boldfaced in the text. For other definitions shown in the text, the term is italicized and the number of the proponent publication follows the definition. ATP 4-33 applies to the Active Army, Army National Guard/Army National Guard of the United States and United States Army Reserve unless otherwise stated. The proponent of ATP 4-33 is the United States Army Combined Arms Support Command.The United States Army is organized, trained, and equipped to be the most decisive land force in the world. Army forces are employed within a strategic context and conduct decisive sustainable land operations through the simultaneous combination of offensive, defensive, and stability or defense support of civil authorities tasks. The Army developed two-level maintenance doctrine to support this type of warfare. In supporting the Army, the primary goal of two-level maintenance is to generate/regenerate combat power and to preserve the capital investment of weapon systems and equipment to enable mission readiness and accomplishment. The commander who combines the skillful use of assigned equipment with an effective maintenance management processes has a decided advantage. The purpose of this ATP is to provide a clear description of the two-level maintenance structure and base operating requirements enabling commanders to provide flexible maintenance support to meet operational objectives. Our Soldiers are trained to perform field-level maintenance. Leaders have to provide time on the training schedule for them to build their skills. Training is the cornerstone to a successful unit support mission by ensuring that ready equipment is available for operations. With all this in mind, leaders must ensure that personnel utilize adequate safety precautions and personal protective equipment in every operation-our Soldiers are our greatest asset. ATP 4-33 has numerous changes from the previous ATP 4-33. The most significant changes are an enhanced discussion on two-level maintenance, updates on other maintenance formations, and an enhanced discussion of Global Combat Support System-Army (GCSS-Army).