Since the 1980s, scholars have called for a new, critical history of the Pharisees. Required is a careful analysis of each source's evidence as a prior condition of historical judgements. By analyzing Flavius Josephus' portrayal of the group, this study clarifies some of the crucial evidence that any hypothesis must explain. Josephus writes about the Pharisees in three of his four extant works, describing their actions under the Hashmoneans, Herod the Great, and during his own tenure as Galilean commander of the revolt against Rome. This study tries to show how his discussions of the Pharisees contribute to his literary aims. With the help of K.H. Rengstorf's new concordance, the author explores the ten pertinent passages in their contexts, supplying also introductory chapters on the Jedean War, the Jewish Antiquities, and the Life. This analysis yields the conclusion that, although the Pharisees were the most popular party in first-century Judaism, Josephus was consistently hostile toward them for reasons peculiar to his own situation.