A model of English intonation is presented in which a variety of intonation contours can be generated from a quantitative prominence labelling of stressed syllables. In one style of speech production, spontaneous speech, a short-lookahead model can generate a variety of contours from the same quantitative prominence labelling. For another style, reading aloud, a long-lookahead model determines the types of intonation patterns associated with texts. These typically come out as sequences of downward-stepping contours, given appropriate initial conditions (though there is no explicit down-step constant in the model). In both styles, the intonation contours are generated on the basis of a quantitative model of contour pitch prominence, in which the pitch prominence of the contour segments which make up the accent contours (and thence the intonation contours) is computed as a nonlinear function of the duration of the contour segment, the ratio of the F0 value at one end of the segment to that at the other, and a rhythm constant.