Considering the spread of computers and the technological advances of recent years, research on persuasive intelligent user interfaces with a fifty-fifty relationship for communicating with humans is necessary. Recently, anthropomorphic user interfaces have been developed, such as virtual agents and robots. To make the interaction between humans and robots more effective, the human must be able to perceive the robot’s actions, manipulate the controls, interpret the robot’s actions, interpret the control information and make decisions on what to do next. This book discusses the principles, technologies and challenges in human-robot interactions.