In order to establish a flexible,reliable and effective joint command & control system,secure and reliable global information network and a high-quality intelligence network,an integrated electronic information system is being developed by US DoD.

This paper comes up with a method of united command and control based on fuzzy arithmetic on the basis of studying many instances and methods in this respect all over the world.

Command and control systems are the kernel parts of command, control,communi-cation,and inteligence(C￣3I)systems.

From the dialectical materialist point of view,this paper expounds the generation background,object and method of study for complicated command and control discipline,as well as its application prospect to related domain,puts forward the proposal concerning how develop a study of command and control in crossing,infiltrating and fusing between disciplines.

As a subject,we try to find out what is its research object,research inclusion,research objective and subject architecture of command and control engineering,we would like to attract more expers to pay attention to this research area,so as to improve the development of science and technology.

This paper expounds the importance and necessity of the command and control system to decision making and further describes and discusses the main matters of decision making,decision making process,structure and system design,evaluation and etc.