||This article has multiple issues. Please help improve it or discuss these issues on the talk page.
In England, at common law, there were "Masters in Chancery," who acted in aid of the Equity Courts. There were also "Masters in Lunacy," who conducted inquiries of the same nature as modern civil commitment proceedings. In the table of precedence for England these two offices rank immediately above Companions of the Bath.
In the United States of America a special master is an "adjunct to a federal court, and Rule 53 of the Federal Rules of Civil Procedure allows a federal court to appoint a master, with the consent of the parties, to conduct proceedings and report to the Court.
United Kingdom 
|This section requires expansion with: section. (October 2010)|
In the High Court of Justice of England and Wales, such an official is usually simply referred to as a Master. Special Masters as a whole provide a mechanism to relieve the burdens related to a heavy caseload for the whole body of judges.
United States 
The role of the special master (who is frequently, but not necessarily, an attorney) is to supervise those falling under the order of the court to make sure that the court order is being followed, and to report on the activities of the entity being supervised in a timely matter to the judge or the judge's designated representatives. Special masters have been controversial in some cases, and are often cited by critics as an example of judicial supremacy over the other branches of government. For example, at times they have ordered the expenditure of funds over and above the amount appropriated by a legislative body for the remediation of the situation being examined. To this point, their powers have generally been found to be valid and their remedies upheld by United States courts.
The United States Supreme Court will normally assign original jurisdiction disputes (cases such as disputes between states that are first heard at the Supreme Court level) to a special master to conduct what amounts to a trial court (the taking of evidence and a ruling). The Supreme Court can then assess the master's ruling much as a normal appeals court would, rather than conduct the trial itself. This is necessary as trials in the U.S. almost always involve live testimony; it would be too unwieldy for nine justices to rule on evidentiary objections in real time.
The usage of Special Masters in matters involving complex electronic discovery (or "eDiscovery") has been promulgated by the Academy of Court Appointed Masters (ACAM).
A court-appointed monitor is a type of Special master.
Cases involving special masters often involve situations where it has been shown that governmental entities are violating civil rights. High-profile cases in recent years where special masters have been utilized include some in which states have been ordered to upgrade their prison facilities, which were held to violate the constitutional provision barring cruel and unusual punishment; and state mental hospitals, which have been found so substandard as to violate the rights of their inmates. Recent cases where special masters have been appointed are discussed in Cohen's Special Master Case Reporter.
In the aftermath of the September 11, 2001, attacks in the United States, then Attorney General John Ashcroft appointed Kenneth R. Feinberg as special master first class to oversee the dispensation of an $11 billion victim's compensation fund.
- Pears' Cyclopædia; February 1932 ed. Isleworth: A. & F. Pears; p. 119
- Text of Rule 53