A special master or master in chancery is an individual appointed by the court to assist with some part of a lawsuit, such as discovery—depositions, written questions, and production of documents—and to make recommendations to the judge on how to resolve related disputes. Courts have held that discovery questions that require extensive examination of highly technical and complex documents by a person having both a technical and a legal background may constitute an exceptional condition sufficient to justify the appointment of a master to supervise such discovery.

In New York, a special master, sometimes referred to as a master in chancery, is an individual appointed by the court to assist in complex aspects of a lawsuit, particularly in the discovery process. This role involves overseeing depositions, managing the exchange of written questions and answers, and handling the production of documents. The appointment of a special master is typically justified under exceptional conditions where the matters at hand are highly technical and complex, requiring expertise that combines both technical knowledge and legal insight. New York courts may appoint a special master when they determine that the complexity of the case is such that it would benefit from the specialized skills of an attorney with the appropriate technical background to manage discovery effectively and to make informed recommendations to the judge. The use of a special master is governed by the New York Civil Practice Law and Rules (CPLR), which provides the framework for their appointment and the scope of their duties.