This manual, "Guard Duty," is for personnel concerned with the organization and functions of interior and exterior guard. It includes orders, countersigns, parole words, and responsibility of the main guard including duties of personnel and methods of mounting the guard. The manual also discusses the duties and composition of special guards. As this manual is a guide, and as all possible situations and eventualities cannot be foreseen or covered by the manual, great reliance must be placed upon the application of sound judgment and common sense by all members of a guard and by all security personnel. In situations not covered by this manual and where doubt arises as to the proper action to be taken, the individual must consider his mission and apply sound judgment in making the required decision(s). The material in this manual is applicable to both nonnuclear and nuclear warfare.