This chapter discusses the economic developments occurring within the Ptolemaic empire (323–30 BCE), of which Egypt was the core province. It explores how state formation affected economic development and how Ptolemaic imperialism, demography, and the interaction between Egyptian and Greek social networks were factors of economic change and economic exploitation. After an overview of past and current approaches to the economy of the Ptolemaic empire and of the geography of the empire, it assesses the cost and benefits of military conquests and the management of migrations patterns and new settlements by the Ptolemies, who increased their revenues and reduced the cost of their army through land allotments to cleruchs. The political economy of the Ptolemies relied on a complex tax system, with some documents pointing to a centralized taxation of the provinces, and innovative but also unusual monetary policies, such as closed-currency system based on a lower weight standard than the Attic standard in Egypt, Cyprus, and Syria-Phoenicia. The chapter concludes with examples of the synergistic relationship between empire, warfare, and trade and between the public and private spheres of the economy, and sketches the purchasing power of different economic groups in Egypt.