The Brazilian Army published the Civil Affairs Field Manual in May 2021, replacing the Civil Military Cooperation Field Manual (2017) and the Government Affairs Manual (1981). Based on the recent doctrinal modification that occurred through the publication of the referenced manual, this study aims to analyze how the process of producing the Brazilian Army s Civil Affairs doctrine took place and how it translates and develops from a set of practices and experiences aimed at improving coordination between civilians and the military in military operations. The study uses a review of specialized literature and the conduct of interviews as methods of qualitative analysis. It is argued that the process of producing civil affairs doctrine is largely based on the experience of the Army military personnel in conducting civil affairs activities in peace operations, humanitarian operations, operations supporting government agencies, in conducting doctrinal experimentation and in the contact of Brazilian military personnel with foreign doctrines through courses conducted abroad, resulting in the use of doctrinal knowledge from partner countries and international organizations. In this way, it can be argued that doctrinal production crosses fields of experiences that combine external and internal military engagement. Additionally, one can conclude that the Manual of Civil Affairs aims to consolidate a doctrine that more objectively informs the Brazilian Army s mission in its relationship with civilian actors.