This chapter considers the principal examples of unconscionability that give rise to constructive trusts. Constructive trusts are imposed when a defendant had knowledge of some factor that should have affected her conscience in relation to property. In English law a constructive trust arises by operation of law. Thus constructive trusts are useful because they achieve the core goal of equity in preventing a defendant from taking unconscionable advantage of another person or of a situation. Constructive trusts may arise in relation to land in three principal ways, all of which illustrate one function of constructive trusts highlighted earlier as a means of supporting voluntary agreements. A thief is considered by the law of trusts to be a constructive trustee of the stolen property from the moment that the theft is committed. A trustee or other form of fiduciary will be a constructive trustee of any personal profits made from that office, even where she has acted in good faith.