An interpreter officer is a commissioned officer of an armed force, who interprets and/or translates to facilitate military operation. Interpreter officers are used extensively in multinational operations in which two or more countries that do not share a common language are undertaking a joint operation, or expeditionary missions in which the communication with the local population is crucial but limited by lack of language proficiency among the expeditionary force personnel. Interpreter officers also work in the intelligence gathering and analysis though in many countries, civilian analysts are used instead of the officers in active duty.