It is now easy to find examples of interactive software agents and animated creatures that have the ability to express emotion; this paper describes research for giving them the ability to recognize emotion. The ability to recognize a person's emotions is a key aspect of human ``emotional intelligence,'' which has been described by a number of scientists as being more important to success in life than are the traditional forms of mathematical and verbal intelligence. This paper describes research underway in emotion recognition at the MIT Media Lab, especially research involving new wearable interfaces.