This is the first volume (text and plates) of the analytically legible seals (ca. 1,162) retrieved through many thousands of full or partial impressions preserved on the 2,087 Elamite administrative tablets recovered during the 1930s excavations at Persepolis, Iran, and published by Richard T Hallock (OIP 92) in 1969. The tablets are dated by date formulae in the texts to the years 509-494 BC in the reign of Darius the Great. Volume I introduces the archive and documents the 312 seals of heroic encounter (retrieved via 1,970 impressions) with high quality composite drawings and a separate volume of 291 halftone and line plate illustrations presented at a scale of 2:1. Entries provide commentary on administrative, social, stylistic, and iconographical features of the seals as well as systematic analysis of seal application patterns. The thirty-four seal inscriptions are presented by Charles E Jones. Twelve appendices synthesize formal and iconographical data and integrate the seals with their associated texts.