In the context of information literacy studies, the research put forward in this paper is focused on the individual and subjective levels of motivation and self-efficacy, together with the sources of learning used by a population of translation students from three Spanish universities. The data were collected by means of the self-evaluating and specific IL-HUMASS survey, and are analysed using a mixed (quantitative and qualitative) case study methodology. From the 26 variables of the survey, the most and least consistent and important ones with regard to motivation and self-efficacy are detected. In general, central tendency scores regarding motivation and self-efficacy increase as respondents advance academically. The most striking opportunities for improvement emerged in relation to the following issues: using bibliographic reference managers, knowing the laws on the use of information, using database managers and communicating in other languages. The surveyed population prefer autonomous learning, with the library being a much underused source of learning.