To learn a foreign language is to enter a new culture. Students who study additional languages learn skills that help them succeed academically or in any other field. They are motivated to learn about the history, geography, art, and music of the people whose languages they are learning. According to Naiman (1978), the most successful learners are not necessarily those to whom language comes very easily, they are those who display certain typical characteristics, most of them associated with aptitude. The present paper has as a main objective to know the constitution of aptitude concerning the learning process of a foreign language. The purpose of this paper is to provide students and teachers with strategies that might improve some weaknesses regarding aptitude. The methodology consisted of a review of studies on foreign language aptitude. The research studied three main areas; the affective variable, the language learning strategies and the learning styles as contributors to aptitude. There was also field work which consisted of the submission of three questionnaires to students. The first questionnaire measured affective variables, the second one was focused on learning strategies and the third one measured learning styles. There was a compilation of the information and an analysis of the findings with their corresponding conclusions which show the characteristics of aptitude concerning the learning process of a foreign language. This work could be useful for students, teachers and syllabus designers.