A liaison officer is a representative placed with another headquarters or organization to improve coordination, communication, and mutual understanding [@jp3_33].
The role matters because command rarely occurs inside a single closed organization. Joint, coalition, interagency, and adjacent-unit action all create seams where information can slow, distort, or lose context. A liaison officer reduces that friction by carrying priorities, constraints, and interpretive context across those seams.
A liaison officer is therefore not only a messenger. The role is part of command and control infrastructure. It helps a force coordinate without pretending that every headquarters shares the same assumptions by default.