Inflammatory and infectious diseases of the pituitary gland are rare, and imaging diagnosis may be difficult. They encompass a wide spectrum of pathology including autoimmune (lymphocytic) hypophysitis, granulomatous hypophysitis, local manifestations of systemic disease, and a multitude of infectious processes. Based on extensive review of the literature, this article will present a classification scheme, description of pathology, and imaging findings of the various inflammatory and infectious entities, along with selected images from our case material.