Equity is a multi-faceted subject, an authentic crossroads of problems. The perspective of this study is, as a result, a mix of focuses, which includes: the philosophy of law, general legal theory, justice theory, the history of law, comparative law, legal dogma, etc. In this book, as in various earlier studies of the author, she uses the "three-dimensional" method, which facilitates a stratified focus in agreement with three levels: facts, norms, and values. The subject of equity has never been analysed as completely as in this work. It includes a dynamic study of the different types of equity throughout history and in the different legal systems; the concept, content, limits, functions and types of equity; the relationship between equity and related ideas, and equity in all the branches of the legal order.