During the second decade of the twenty-first century, documentation in electronic format has come to form a normal part of the workplace for all professional translators. The aim of this article is to present the results of the acquisition of the instrumental sub-competence, which is based on the use of electronic resources. These results are part of empirical-experimental research carried out by the PACTE group on Translation Competence Acquisition. In this study, the evolution of the acquisition of this sub-competence for five groups of translation students, from the first year of their degree course to their entry into the labour market, was measured using a methodological design that simulates a longitudinal study. The experiment was carried out in 2011 with 130 students on the Translation and Interpreting degree course. Five indicators related to the direct and inverse translation processes are analysed: number of resources, time taken on searches, time taken on searches at each stage, number and variety of searches. These indicators are then correlated with the quality of the final product of the translation process: translation acceptability. The results produced by the translation students are compared with those obtained in the Translation Competence experiment, carried out by the PACTE group in 2005−2006 with 35 professional translators