SummaryThere is currently a great deal of interest in the development of intelligent agents. While there is little agreement on exactly what constitutes an intelligent agent, many definitions embody a user interface model that differs from the traditional one where users perform tasks with the help of computer-based "tools." In contrast, the "delegation" model associated with agents is based on entrusting tasks to an autonomous, sometimes anthropomorphized system, whose performance is monitored and evaluated. This change in user interface model is a dramatic one since delegation can be a difficult and often-avoided behavior in humans. Agent interface designs need to overcome well-established drawbacks in delegation. For this purpose, designers should find the management sciences and organizational psychology literatures to be as relevant as that of traditional human factors. This paper describes issues regarding task delegation as they pertain to the design of intelligent agent user interfaces.