ATP 3-13.3 governs operations security for protecting essential elements of friendly information during combat operations at division and below.
View ATP 3-13.3 on armypubs.army.mil
It covers OPSEC fundamentals, the staff OPSEC process, threat and vulnerability analysis, risk assessment, countermeasures, and the military decisionmaking process. It also addresses reviews, assessments, surveys, documentation, and tips for developing an operations security appendix.
Applies to: the primary users of this publication are tactical unit commanders, operations security planners, and staffs.
Army security programs focus on classified information, but OPSEC focuses on protecting unclassified information, which includes denying essential elements of friendly information to our enemies and adversaries. (paragraph 1-3)
OPSECs overarching goal is to eliminate, reduce, or conceal unclassified indicators that could compromise both classified information as well as essential elements of friendly information about an Army unit. (paragraph 1-3)
Because the OPSEC planner and security manager are separate positions with distinct goals, they should be filled by different people. (paragraph 1-3)
Effective and disciplined OPSEC is employed during all decisive actions. (paragraph 1-5)
An OPSEC review is a documented evaluation of information or visual products intended for public release to ensure protection of essential elements of friendly information. (paragraph 4-2)