Based on self-determination theory, we conducted an exploratory study aimed at identifying teachers' beliefs about motivation and motivating practices in second-language teaching at a private language center in Medellin, Colombia. To gather data, 65 teachers were surveyed; from this initial group, 11 were interviewed and observed in class during 2012. The results show that teachers' potential to promote motivation is mostly centered on relatedness and that while teachers recognize the positive and beneficial effects of promoting autonomy and competence, their teaching practices do not evidence those beliefs. Based on the results, we conclude that in order to promote autonomy and competence, it is important, first of all, to establish the right social conditions, i.e. meaningful teacher-student relationships.