A trust is a fiduciary relationship in which one person is the holder of thetitle to property subject to an equitable obligation to keep or use the propertyfor the benefit of another. The second part of this thesis introduces the estatesin land under the English Feudalism to be the background of the origin of thetrust. Part three explains the beginning of uses and their evolutions to realizethe forming process of trusts. Part four narrates the formation of trusts andtheir meanings. Part five explores trusts in modern Common Law in order toknow their developments. Part six explores the development of trusts in the20th Century to amplify practical functions of trusts. This thesis, in conclusion,emphasizes that the core concepts of trusts induced from the origin and develop-ment of trusts are what the fundamental knowledge we should know when ourcountry adopt trust law, and only with this fundamental knowledge do weappropriately interpret and apply the Trust Act.