The quest for innovations and fascination for learning has led to revolution in every field and Dentistry is no exception. Perforation repairs, apexification, root end fillings, pulp therapies, surgical and non surgical are few of the procedures which are performed regularly with predictable prognosis in dentistry. As it is rightly said "Necessity is the mother of Invention", the need for an ideal material with predictable seal ability, good biocompatibility, increased moisture sensitivity and healing ability led to development of MINERAL TRIOXIDE AGGREGATE, a new material with innumerable clinical applications in Endodontics. Mineral Trioxide Aggregate (MTA) was developed by Dr.Mahmoud Torabinejad at Loma Linda University, California in the year 1993, as a root end filling material. This book will introduce clinicians to various applications of MTA that might improve the healing outcomes for patients presenting with complex and challenging endodontic conditions.