A Grammar of the Ancient Egyptian Pyramid Texts is designed as a six-volume study of the earliest comprehensive corpus of ancient Egyptian texts, inscribed in the pyramids of five pharaohs of the Old Kingdom (ca. 23252150 BC) and several of their queens. The first volume, devoted to the earliest corpus, that of Unis, is based on a database that allows for detailed analysis of the orthography of the texts and every aspect of their grammar; it includes a complete hieroglyphic lexicon of the texts and a consecutive transcription and translation on facing pages. The grammatical analysis incorporates both the most recent advances in the understanding of Egyptian grammar and a few new interpretations published here for the first time.