In this article, we analyze the relationship between studies in second language acquisition and studies in bilingualism as areas that have been traditionally ignored but which share some common perspectives. Then we look at new trends in both areas that are compatible with a holistic perspective in the study of multilingualism. Based on these trends, we propose "Focus on Multilingualism," an approach that looks at the whole linguistic repertoire of multilingual speakers and language learners and at the relationships between the languages when conducting research, teaching, or assessing different languages. In the second part of the article, we report on the results of an exploratory study on the development of writing skills in three languages: Basque, Spanish, and English. We explore different ways to look at the three languages and their interaction by focusing on the multilingual speaker and his or her languages rather than each of the specific languages in isolation. The results indicate that the languages are related to each other in different ways and that multilingual speakers develop their creativity in these language practices. We argue that by focusing on the different languages, we can gain new insights about the way languages are learned and used.