Dictionaries can be effective learning tools, capable of promoting learning autonomy to fill the gap left by an inefficient education for instance. The functional quality of these works is, however, tied to a good understanding of the profile of their intended users. In the field of lexicography, this understanding can be achieved by means of user-studies. Currently, most EFL dictionaries target a very generic profile - English learners - and neglect the fact that learners from different cultures and linguistic backgrounds may have different needs and preferences. This thesis presents and discusses the results of a lexicographic user-study conducted in Brazil with 61 English learners. The objective of this study was to investigate the profile of Brazilian learners of English as a target-group for EFL dictionaries. The study combined two methods of investigating dictionary use: written protocol and questionnaire. Through the written protocol, data about participants’ look-up strategies and samples of their performance in both receptive and productive EFL tasks were collected. The questionnaire gathered information about participants’ socio-cultural background and their consultation preferences. All data were analysed as follows: principles of Error Analysis were used to build a taxonomy capable of classifying participants’ errors resulting from reference source consultation (meaning, grammar, spelling or usage). The taxonomy was built based on the premise that it can be a valuable way of identifying the weakness of EFL learners in order to develop a dictionary to address their needs. With the results of this classification, it was possible to identify participants’ most frequent difficulties when performing EFL tasks. Once participants’ errors were located and classified, information about their look-up strategies was used to retrace the consulted reference source in order to find clues to explain why the consultation resulted in error. Finally, participants’ self-reported behaviour in the questionnaire was compared to their actual behaviour in the experiment. The results of this user-study suggest that both linguistic and socio-cultural background have an impact on learners’ expectations about dictionaries, their preferences, and the difficulties they experience while trying to access relevant linguistic information. The outcomes of this study shed light on the average profile of the Brazilian learner of English and it would be useful for other investigations towards the development of a lexicographic reference source to address the specific needs of this target group
