Students from the English as a Foreign Language (EFL) Program targeted in the present study are expected to achieve a C1 level of English proficiency according to the Common European Framework (CEF). However, only a five per cent of the students has evidenced this level on the institutional English exam (Ileusco Test, henceforth IT) for the past five years. Through the present descriptive-exploratory qualitative study we have attempted to inquire about the personal and academic factors that may have contributed to the successful development of the L2 competence of those learners.We used a questionnaire, individual interviews and focus-group interviews to ask 12 students about learning strategies, experiences and actions they have implemented to develop their l2 competence. We concluded that it is mainly students' commitment and self-discipline that helped them keep their L2 learning process successfully running; that despite the high quality of a school curriculum, a language program or a teaching methodology, it is students' autonomous learning initiatives that mainly enhance their L2 proficiency; and that L2 instruction in higher education seems to convey a stronger impact than elementary and secondary education.