Prisoner’s Dilemma refers to a game that forces people to choose between cooperation and competition; mixed-motives dilemma in which everyone is better off cooperating, but cooperating with a competitive partner brings personal disaster. The Prisoner’s Dilemma is a concept in game theory which is used to illustrate a variety of situations. The concept is also sometimes utilized in fields like psychology and philosophy, when people want to examine why people act in the ways that they do. Credit for the development of the prisoner's dilemma is generally given to a pair of RAND researchers, Merrill Flood and Melvin Dresher, who worked in the 1950s. Albert W. Tucker refined the idea, and christened the concept "Prisoner’s Dilemma"