The term logistics covers a wide range of activities and capabilities, some of which are more closely related to each other than others. They may be grouped into the following categories:

1. 1. Supply. Supply entails providing combat forces with the fuel, ammunition, spare parts, equipment, food, water, and other materials they need to operate. It also entails providing other logistics organizations, such as those responsible for repair and maintenance, mobility, engineering, and health care, with the tools, equipment, spare parts, blood, and other materials they need to perform their functions.

2. 2. Repair and maintenance. Repair and maintenance entails keeping weapon systems, vehicles, and other equipment in good working condition as well as repairing them, either in the field or at rear area depots, when they become damaged.

3. 3. Mobility. Mobility refers to moving combat and support units from one location to another (when such movement involves other than the organic movement capabilities of the moving units, such as the ability of a tracked vehicle to move cross-country or the ability of a soldier to walk). Note that many of the assets used for mobility can also be used for performing other logistics functions, such as delivering supplies, moving damaged equipment to rear area depots for repair and returning it when repaired, and evacuating injured and dead personnel to medical facilities and morgues.

4. 4. Engineering. Engineering includes activities such as constructing and repairing roads, railroads, bridges, airfields, seaports, base camps, and other facilities.

5. 5. Health services. Health services include both keeping personnel healthy (through vaccinations, regular examinations, etc.) and treating the wounded, injured, and sick.

6. 6. Other logistic services. Other logistic services include preparing food, providing hygiene services, operating base camps, and so on.

A common saying in military circles is that “Amateurs talk about strategy and tactics; professionals talk about logistics.” Thus, the importance of logistics to the success of military operations is well recognized. As in the case of training, however, students of military affairs do not appear to have developed a general theory of the characteristics of good logistical support. The issue is further complicated by the diversity of activities included under the rubric of logistics. The approach taken in this chapter, therefore, is simply to attempt to assess the principal factors that can affect the PLA's capability to conduct each of the five main types of logistics support listed above (supply, repair and maintenance, mobility, engineering, and health services).