Extempo (also extempo calypso) is a lyrically improvised form of calypso and is most notably practised in Trinidad and Tobago. It consists of a performer improvising in song or in rhythmic speech on a given theme before an audience who themselves take turns to perform. It is inherently competitive and success is judged by the wit and ingenuity of the performance.
It is similar in form to what has been defined as traditional African song: "a recitative or chants with a short chorus. The soloist gives the melody while a chorus sings a refrain. As the melody is given out, they turn to one another, each improvising in turn. Extempo tends to comprise topics from current events treated with mockery, ridicule and sarcasm, or with flattery or praise.”
It is characterised either by the “single tone”, consisting of four-line stanzas or the “double tone”, which has eight-line stanzas. There are four basic melodies common to extempo: “Sans Humanite”, “Matilda”, “Miss Mary Ann”, and “Big Bamboo”. The most widely used is "Sans Humanite". Another characteristic of extempo is that the performer must be able to think quickly since the subjects are handed out on the spot and the lyrics are then improvised.