Over 70 studies on human-machine interaction in the last decade have pointed to an intriguing phenomenon: People interact with machines in a way that is basically social, even when the interaction was not designed to be that way. This program will describe how we’re giving computers some social skills, specifically the ability to recognize and respond appropriately to human emotion. Examples are shown on keyboard-mouse-monitor systems that try to assess user frustration for usability feedback, and wearable systems that classify affective state based on skin-surface measurements. From the Series:CSE Colloquia - 2001