Taaj ul-Aqaa'id is a well known treatise compiled by the 5th Da'i ul-Mutlaq Saiyedna Ali bin Mohammad al-Waleed (QR) (605-612 AH/1208-1215 AD) in Yemen . He is also the author of many other works which are regarded as very authoritative and are still studied by the Isma'ilis . The book describes the principles and beliefs, which belong to the practice of Isma'ili religion. The book is divided into a hundred “aqaa'id” (pl. of ‘aqeedah meaning belief). Each belief has its number, and the main subject of the note indicated in a heading. In his introduction the author states that, “as there are many heretical movements in the Isma'ilism , and much danger of the pious falling into error, great need is felt for a work which would give a clear ides as to what is the true religion of the Isma'ili Imaams”. All the Isma'ili believes and abides to the principles as mentioned in the book. Here we present you the English translation of the principles (Aqeedah) in parts, each quoting 15 principles.