The purposes of this study were, on one had, to determine the impact of a peer tutoring program on preventing academic failure and dropouts among first-year students (N = 100), from Civil Engineering, Economics, Pharmacy, and Chemical Engineering careers; while, on the other hand, to identify the potential benefits of such tutoring program on the cognitive and metacognitive learning strategies and social skills of student mentors in their last year of studies or already in a postgraduate program (N = 41) at the University of Granada (Spain). After building and selecting the measurement instruments necessary to gather demographic and academic relevant information on both samples, and assigning first-year students to either an experimental or control group, the intervention consisted of ten 90-min tutoring sessions during the first semester lead by student tutors who, in turn, had undergone four 3-h training sessions on tutoring contents like planning and time management, cognitive and metacognitive learning strategies, motivational strategies and the use of materials designed "ad hoc" for this program. The results show differences in favour of the treatment group on grade point average, performance rate, success rate and learning strategies and, also, statistically significant pre-post differences for the tutors on learning strategies and social skills.