Investor Relations (IR) is a strategic management responsibility that integrates finance, communication, marketing and securities law compliance to enable the most effective two-way communication between a company, the financial community, and other constituencies, which ultimately contributes to a company's securities achieving fair valuation. (Adopted by the NIRI Board of Directors, March 2003.) The term describes the department of a company devoted to handling inquiries from shareholders and investors, as well as others who might be interested in a company's stock or financial stability.

Typically investor relations is a department or person reporting to the Chief Financial Officer or Treasurer. In some companies, investor relations is managed by the public relations or corporate communications departments, and can also be referred to as "financial public relations" or "financial communications". Investor relations is considered a specialty of public relations by the U.S. Department of Labor.

The investor relations function must be aware of current and upcoming issues that an organization or issuer may face, particularly those that relate to fiduciary duty and organizational impact. In particular, it must be able to assess the various patterns of stock-trading that a public company may experience, often as the result of a public disclosure (or any research reports issued by financial analysts). The investor relations department must also work closely with the Corporate Secretary on legal and regulatory matters that affect shareholders.

While most IROs would report to the Chief Financial Officer, they will usually also have access to the Chief Executive Officer and Chairman or President of the corporation. This means that as well as being able to understand and communicate the company's financial strategy, they are also able to communicate the broader strategic direction of the corporation and ensure that the image of the corporation is maintained in a cohesive fashion.

Due to the potential impact of legal liability claims awarded by courts, and the consequential impact on the company's share price, IR often has a role in crisis management of, for example, corporate downsizing, changes in management or internal structure, product liability issues and industrial disasters.

The most highly-regarded professional member organization for Investor Relations in the United States is the National Investor Relations Institute, or NIRI.