This special issue is made up of five articles which cover the emerging area of human-robot interaction. The first paper offers a theoretical ecological framework for the design of personal service robots in homes of elderly people. Next, a field study of two robots that visited a children's elementary school in Japan for two weeks, with the purpose of teaching children English, is presented. The third article reports on an opportunistic field study of search and rescue robots used as part of a night rescue training exercise. A different perspective on human-computer interaction for search and rescue robots is discussed in the fourth paper. Finally, an experimental laboratory study is presented that explores how people who have to work closely with professional service robots will perceive and work with them. Taken as a whole, these articles represent some of the first systematic empirical research in human-robot interaction.