Studies of laughter are spread over multiple scientific disciplines of which many have nothing or nearly nothing in common: from conversational analysis and interactional linguistics to emotional psychology, from phonetics and speech technology to physiology, from evolutionary biology to cultural studies. There is not a single established laughter research community but several interest groups that were and still are emerging in parallel. Thus, the many different facets of laughter lead to a big diversity of research foci of which only a selection can be treated in this chapter.