Which document type primarily functions as a time-sensitive directive?

The document type that primarily functions as a time-sensitive directive is a DTM, or Directive-Type Memorandum. DTMs are designed to provide immediate guidance, implement policy updates, or direct actions in a timely manner when needed. They often address urgent situations and can cover a wide range of subjects, including changes in procedures, urgent policy clarifications, or interim guidance.

In contrast, the other document types serve different purposes. For instance, DoDDs (Department of Defense Directives) establish policies and objectives and often have a longer-term focus without the immediate urgency that characterizes DTMs. DoDIs (Department of Defense Instructions) provide detailed procedures and directives to implement the policies set forth by DoDDs but are also not inherently time-sensitive. DoDMs (Department of Defense Manuals) offer comprehensive guidance and operational procedures; they serve as reference materials rather than immediate directives. Therefore, the DTM stands out as the most suitable answer when dealing with time-sensitive directives.