The book deals primarily with legislation and the rules for the legislators to follow to arrive at the most reliable judgments in issues of law. Imam al-Shafi'i ((150/767 - 204/820)) was the founder of the school of law followed by students for centuries through the present day.

Dr. Ali Bin Wanis's critically explained and edited edition of the Risalah of Imam al-Shafi contains explanations on various terminology, references of Hadith with grading of authenticity, in an easy to follow format for a serious student of this monumental work, one of the first in the studies of Principles of Jurisprudence or Usul al-Fiqh.