The chapter deals with the metaphysical section (Ilāhiyyāt, “Science of Divine Things”) of Avicenna’s philosophical masterpiece Kitāb al-Šifāʾ (Book of the Healing), discussing preliminarily its presumed date of composition and place within Avicenna’s biography, and its distinctive traits with respect to other works of Avicenna dealing with metaphysics. Three further issues are then primarily addressed: the Ilāhiyyāt as a prime example of the idea that the science of metaphysics is first among the philosophical disciplines and possesses epistemological unity despite its internal articulation; the philosophical sources of the work, both in ancient Greek philosophy and in Arabic pre-Avicennian falsafa, and the cultural setting in which the Ilāhiyyāt is meant to circulate as well as its intended audience; its main doctrines, pertaining both to ontology (the doctrine of being qua being and its afferents) and to philosophical theology (God’s existence, nature, and agency).