This document defines fiqh and usul fiqh, and their importance in Islamic law (shariah). Fiqh refers to the body of Islamic law pertaining to human conduct and rulings derived from primary sources. Usul fiqh comprises the principles by which legal rulings are derived, such as qiyas (analogical reasoning) and the hierarchy of evidence. The document outlines the process a mujtahid (legal scholar) undertakes and sources considered to issue new rulings. Fiqh and usul fiqh are important for Muslims to understand religion fully, know how rulings are reached, and apply law to conduct according to Islamic guidelines.