This volume of the series “Shia Islam” has been written to present the basic viewpoints of Shia Islam on justice, which are of particular importance in our age: - to be presented transparently, - to show the way to her, - to follow her faithfully, - become familiar with justice as the basis for peace, - to promote good human coexistence. The topic is treated here neither from a secular nor from a revelatory religious perspective, but exclusively from the perspective of Shia Islam. Justice, i.e. “Idalah”, is explained by the word “Adl”, which is used both as a term and as a principle. As a term, justice has two main definitions, namely: a. to give each one what is his right. b. to put him in the place he deserves. Because of the importance of justice and its study to explain the balance and its share in creation, as well as the recognition of the attributes of the sublime Creator (“that He is just and reigns with justice), it has been repeatedly emphasized in Islam. Two important words of: - justice (العدل) and - balance/equality (القسط) were used to express the concept of justice more accurately. Traditionally justice has been divided into the following main titles: - divine justice, - individual justice, and - social justice.