The PLISM is usually assumed to be an Intergalactic alliance of worlds, although the extent of its influence is not certain.  It is commonly agreed among Imperial scholars that the Cylexian race plays at least a minor role in the central government of the organization.  The style of government employed by the PLISM is uncertain, although it is obvious that a high level of centralization is a likely feature.  The PLISM is known to possess higher technologies than any of the other local governments, but the details of these technologies are unknown.

In the explored galaxy, the PLISM is subdivided by the Interstellar Cartographic Survey Division into Eastern and Western territories.  Selesil appears to be the primary star system found in the west.  Protraxis is believed to be the dominant system in the east.  This cannot be confirmed, however, as neither system has been visited.