Master's thesis supervision is a complex task given the two-fold goal of the thesis (learning and assessment). An important aspect of supervision is the supervisor-student relationship. This quantitative study (N = 401) investigates how perceptions of the supervisor-student relationship are related to three dependent variables: final grade, perceived supervisor contribution to learning, and student satisfaction. The supervisor-student relationship was conceptualised by means of two interpersonal dimensions: control and affiliation. The results indicated that a greater degree of affiliation was related to higher outcome measures. Control was positively related to perceived supervisor contribution to learning and satisfaction, but, for satisfaction, a ceiling effect occurred. The relation between control and the final grade was U-shaped, indicating that the average level of perceived control is related to the lowest grades. The results imply that it is important for supervisors to be perceived as highly affiliated and that control should be carefully balanced. (Contains 3 tables and 3 figures.)