This dissertation makes a comparison of language and music. As composer Lerdahl and linguist Jackendoff show in their ‘Generative Theory of Tonal Music’, these two cognitive behaviors share aspects, such as hierarchical structure, in which prominent elements are separated from non-prominent elements by means of preference rules and rhythmic and phrasing phenomena. Recent constraint-based approaches to phonology, such as Optimality Theory, show that the similarities are even more striking for phonological and musical analyses. This dissertation shows that music theory may help to solve linguistic issues with which linguistic theory alone finds it hard to deal. Three such issues are investigated experimentally. The first issue is whether speech is just shortened and compressed when people speak faster, with the same rhythmic structure, or whether the speech rhythm changes. The second issue is the question whether recursion can be found in phonology. Are phrasing phenomena such as early accent placement applied repeatedly in embedded phonological phrases? The third issue is major and minor modality in intonation contours of cheerful and sad speech. One of the main findings is that listeners appear sometimes to base their perception on auditory illusions, not always on the sound signal as it is. Listeners hear what they expect to hear. As in music, rhythm is perceived as more regular than it is in reality. The results of this research confirm the assumption that speech and music share many features. Both are ‘made of’ sound, and both kinds of sound signal are structured by the listener in a similar way.