Translating specialized texts requires specific competences that involve acquiring knowledge about the domain, about the terminology and about the textual genre and stylistic conventions present in source and translation texts. In this process, specialized documentation is crucial because it allows to compensate the lack of expert knowledge by searching for information in specialized documentation sources and helps solving a great part of translation problems. This article explores the development of specialized documentation competence in translation students of a Chilean university across their training. Second, third and fourthyear students carried out two tasks involving thematic and terminological documentation of a medical research article. Results showed that more advanced students are able to identify more relevant resources, to better judge their reliability and to perform more complex search strategies, associated to different stages of the translation process. The better performance of the advanced group is explained by their broader experience in specialized translation practice.