A person who undertakes to act on behalf of or for the benefit of another is called a:

A person who undertakes to act on behalf of or for the benefit of another is termed a fiduciary. This role involves a legal and ethical obligation to act in the best interest of another party, often established through a relationship characterized by trust and confidence. In financial contexts, fiduciaries include agents, trustees, and financial advisors who manage assets and make decisions on behalf of clients or beneficiaries. The fiduciary is responsible for ensuring that their actions align with the best interests of those they represent and must place the interests of their clients above their own.

For instance, in a trust arrangement, the fiduciary (the trustee) must manage the trust's assets responsibly and follow the terms set forth by the trustor, ensuring that the beneficiaries receive their entitled benefits in a manner consistent with their interests. This principle of serving another's interests is foundational in many professional relationships, particularly in finance, where duties of loyalty and care are paramount. Understanding this concept is crucial for anyone participating in the financial services industry, as it underscores the importance of ethical conduct and accountability in fiduciary relationships.