In recent decades, a number of local archives and other primary sources for the history of the Achaemenid empire have been made available for the first time, or have received new treatment. Foremost among these are the Persepolis Fortification archive and the correspondence between the satraps of Bactria and Egypt and their respective staffs. Several contributors to this volume try to analyze the events and transactions documented by these sources in terms of bureaucratic and administrative protocols and to interpret them within an empire-wide network. Recurring patterns reveal a system of administrative hierarchies and structures. Among other things, the Achaemenid administration managed supplying official travelers, assuring regular communication between the empire's core and the provinces, and it used some of the same methods and institutions to manage supply, assignment and logistics of workers sent from the provinces to do labor service in the center of Persia. Another approach represented in this volume confronts these primary sources with information about Achaemenid imperial administration in classical sources, the primary material serving both as corrective and as analytical tool. Combined, these complementary approaches lead to a similar assessment: the imperial administration was not characterized by rupture and ad hoc responses to crises but rather by continuity and stability, and these long-term factors were important reasons for the unprecedented scope and endurance of this first world empire.