Kitab al-Hawi is a comprehensive medical text written by the Persian physician Al-Razi, also known as Rhazes, in the 9th century. It serves as an encyclopedia of medical knowledge, compiling various treatments, diseases, and medical theories of the time. The work is notable for its systematic approach and emphasis on clinical observation. The text is divided into several sections, covering topics such as surgery, pharmacology, and the diagnosis of illnesses. Kitab al-Hawi played a significant role in the development of medical science in the Islamic Golden Age and influenced later European medicine during the Renaissance.