The intonation systems of many languages apparently allow gradient linguistic categories by the side of discrete or categorial contrasts. It is argued that these gradient meanings arise when the intonational phonology leaves a certain amount of unused phonetic space, which may be exploited by speakers to convey "meanings" which are naturally associated with nongradience linguistic pitch variation. Because these meanings are often similar to the linguistic meanings attached to the phonological intonational categories, intonation the issue of gradience versus discreteness is more difficult in intonation than in other linguistic domains. Three experimental techniques that can be phonology used to investigate the gradient or discrete nature of intonational differences, the "semantic task," the "imitation task," and the "pitch range task," are discussed and evaluated. In addition, it is pointed out, following an earlier discussion by Newport, that categorical perception is a sufficient, but not a necessary, property of phonological discreteness.