There are planets in every sector in the Empire which cause more than their share of problems for the Emperor. Controlling these worlds is difficult, and the Moffs have found that the troubles are infectious, spreading from system to system from the source. The situation is made more difficult by the fact that the infection of freedom has no respect for sector boundaries; coordinating efforts between sectors is often impossible to accomplish in time to stop the spread of unrest. The Moffs have the resources to handle crises on a dozen or more worlds, but if the trouble cannot be contained to those planets, the Empire’s grasp on an entire sector may be weakened.
Taking the advice of one of his Moffs, Tarkin, the Emperor formed priority sectors. A priority sector is a sector consisting of systems on which signs of unrest have recently been detected, or systems which are in regular contact with systems in which unrest is chronic. A priority sector often crosses the boundaries of standard sectors, containing the worlds from a dozen or more sectors. The title of Grand Moff is also granted to the being in charge of a priority sector.
The theory behind priority sectors, codified in the Tarkin Doctrine, is that Grand Moffs will be able to react quickly to problems when they are small, eliminating them before they have a chance to grow and spread. Grand Moffs are therefore given complete freedom to act as they see fit, without giving advance warning to the Moffs or planetary governors of their actions.
The number of Grand Moffs is growing, and the resources given to each Grand Moff is also increasing. The Emperor personally appoints each Grand Moff, and they report directly to him. Each Grand Moff commands at least two Sector Groups, or the equivalent in other military resources. Some Grand Moffs are given even greater military strength if their priority sector is of crucial importance to the Empire.
Priority sectors are the first to receive experimental equipment, and theirs are the first to have losses replaced. Priority sectors are sometimes given special missions in which the Emperor has a personal interest. The Death Star Project is an example of a priority sector into which the Empire poured resources enough to have formed perhaps a score of Sector Groups.
The Moffs and planetary governors have politely complained about the favoritism shown Grand Moffs, arguing that the Grand Moffs are of- ten completely unfamiliar with the systems in their jurisdiction and take actions which only work in the short run. The governors and the Moffs claim that they are then stuck with the problems caused by the Grand Moffs, yet get fewer resources than they ought to have to implement a solution. The Moffs point specifically to the situation at Yavin as the prime example of a Grand Moffs failure. The Emperor, however, will hear none of it.