SecondinCommand

The second in command, abbreviated 2IC or 2iC, is the principal assistant and deputy to a commander in a hierarchical organization. The 2IC is responsible for helping to lead, plan, and coordinate operations and serves as the designated successor should the primary commander be unavailable or incapacitated. The role appears in military, police, emergency services, and some corporate or organizational structures, where a formal deputy or chief of staff exists alongside a commander.

Typical duties include assisting with strategic and tactical planning, supervising staff, overseeing training, administration, and logistics, monitoring readiness, and ensuring discipline and welfare within the unit. The 2IC often acts as a liaison between the commander and subordinate units, communicates orders, and may assume day-to-day command in the commander's absence or during transitions. In many organizations, written standing orders or a commander's instructions outline the scope of the 2IC's authority.

Selection and authority vary by organization. The commander generally appoints the 2IC and defines the extent of delegated authority. The 2IC is expected to be loyal, trustworthy, and capable of independent judgment, while respecting the chain of command. In emergencies, established protocols may allow the 2IC to exercise full command authority until the commander is able to return.

Outside formal military use, the term persists in popular culture and in some corporate environments as a descriptive title for a deputy leader, though terms such as deputy, vice, or chief of staff are more common. The concept of a second-in-command remains a core element of leadership design, aiding continuity and operational resilience.