The texts collected in this volume study the phenomenon of ambiguity from different perspectives, both language “internal”—in relation to the grammatical system and its contextualized use—and language “external”, especially in the philosophical and legal fields. Likewise, ambiguity is also discussed from the point of view of functional variation and applied linguistics. The works derive from the presentations and the roundtable that took place at the thirty-first edition of the Col·loqui Lingüístic de la Universitat de Barcelona (CLUB 31) on 27 October 2023, under the title “L’ambigüitat: un enfocament interdisciplinari”, and were originally published in Catalan within the volume L’ambigüitat: nous camins, velles fronteres. In the first article, Jordi Fortuny and Lluís Payrató present the property of linguistic indeterminacy, according to which linguistic expressions do not determine all aspects of their interpretation. In the second article, Pompeu Casanovas discusses the relationship between linguistic pragmatics and the expressive conception of law. In the third article, Manuel García-Carpintero analyzes how certain philosophical currents such as externalism, among others, understand gender terms like male and female. In the last article, Mariona Taulé and Mireia Farrús offer a vision of the challenges presented by ambiguity in the field of technologies applied to written texts, oral language and speech.