The ramified monetary system of the Attalid kingdom is described and its relationship to other monetary systems of the eastern Mediterranean in the Hellenistic period explained. The character of the cistophoric coinage was neither fully royal nor civic, but should rather be understood as a “coordinated coinage” that required the cooperation of both polis and Attalid authorities. Local monetary needs could dictate the shape of the money supply, as in the signal case of Tralles. The burden and profits of epichoric coinage at regional scale were shared, while the kings ceded symbolic space on the coin types for representations of civic identity. Cooperation can also be glimpsed in countermarks and proxy coinages. Unlike Ptolemaic Egypt, the Attalid kingdom was not a closed currency zone, though the cistophori helped integrate vast new territories. Their reduced weight standard economized on silver, but Pergamene mines existed in Anatolia and should be factored into explanatory models.