This paper deals with the basic aspects of the functionalist approach, taking as an example a study of more than 12,500 book titles in German, English, French and Spanish. Working on the principle that book titles are idiosyncratic textual units and constitute a textual type or genre, the author analyses different linguistic and pragmatic aspects: the communicative functions which a title has to perform, the stylistic resources used to verbalize those functions in every culture or the structural conventions of this text-type. To conclude, the article summarises the basic conditions for the functional translation of titles to become a paradigm of functional translation of texts in general.