A fiduciary is a person who holds a legal or ethical relationship of trust with one or more other parties. Typically, a fiduciary prudently takes care of money or other assets for another person. One party, for example, a corporate trust company or the trust department of a bank, acts in a fiduciary capacity to another party, who, for example, has entrusted funds to the fiduciary for safekeeping or investment. Likewise, financial advisers, financial planners, and asset managers, including managers of pension plans, endowments, and other tax-exempt assets, are considered fiduciaries under applicable statutes and laws. In a fiduciary relationship, one person, in a position of vulnerability, justifiably vests confidence, good faith, reliance, and trust in another whose aid, advice, or protection is sought in some matter. In such a relation, good conscience requires the fiduciary to act at all times for the sole benefit and interest of the one who trusts.A fiduciary is someone who has undertaken to act for and on behalf of another in a particular matter in circumstances which give rise to a relationship of trust and confidence.

In the field of jurisprudence, equity is the particular body of law, developed in the English Court of Chancery, with the general purpose of providing legal remedies for cases wherein the common law is inflexible and cannot fairly resolve the disputed legal matter. Conceptually, equity was part of the historical origins of the system of common law of England, yet is a field of law separate from common law, because equity has its own unique rules and principles, and was administered by courts of equity.