The volume under review brings together 40 chapters written by 30 contributors concerned with ancient astronomy in the Near East and the Mediterranean. As a "Companion" volume, it creates the expectation that it will provide an overview of relevant historical evidence as well as a summary of consensual knowledge and ongoing debates in the field. This is certainly the case for most of the chapters, and thus the volume offers a welcome point of departure for non-specialists as well as a useful bridge between various areas of specialization such as Egyptology, Assyriology, and Greek and Roman studies.In their "Preface" and "Prolegomena," the editors state that their purpose was twofold: "the description and analysis of Hellenistic astronomy as an exact, or mathematical, science" and "to emphasize as well its cultural reach and, in particular, the central role played by astrology" (p. xvi). Departing from common usage, they define "Hellenistic" as "the period from the late fourth century BCE," when "Babylonian mathematical astronomy and astrology" began to instigate a "great change" in Greek "astronomical theorization," "to the mid-eighth century CE," "when the Arabs took Greco-Roman science in new directions" (p. 3). At page 6, they include within the geographical range of the study "the various regions brought into contact by Alexander the Great"; yet this would imply, at least, a chapter each on Sanskrit and Syriac astronomy. Other conspicuous absentees are Latin astronomy after the fall of the Western Roman Empire (for example, Gregory of Tours), and Greek astronomy after the decline of Alexandria (for example, Stephanus of Alexandria).Although much ground is well covered, some topics are arguably missing: thus, in describing ancient astronomy, only passing reference is made to the possibility of heliocentrism; in contextualizing it, no mention is made of the astronomical features of buildings, as studied by archeoastronomy. Without multiplying examples, suffice it to say that the Hellenistic period in its conventional definition (323-30 BCE) would have provided quite enough material for a companion volume on astronomy and its cultural contexts. On the other hand, chapters occasionally overlap and may even contradict each other (for example, pp. 31-33 and Chapter 9.2 on the Antikythera mechanism).The difficulty of providing an adequate overview for an entire millenium's worth of history across several cultures is one possible explanation for some major gaps in the bibliography. One might have expected some reference to founding figures like Paul Tannery and Carl Bezold. Many recent scholars have also gone missing-to name but a few