In this paper general practitioners' (GPs') somatic-psychosocial attributions of fatigue are examined. The attribution process during medical consultations was studied by relating the GPs' judgements of the somatic-psychosocial character of their patients' fatigue to patient-related characteristics, on the one hand, and medical-consultation characteristics on the other hand. The study was based on 2097 contact registrations from the Dutch National Study of Morbidity and Intervention in General Practice by the NIVEL (Netherlands Institute of Primary Health Care). In order to explain the GPs' attributions, patient-related characteristics were added stepwise in a multiple regression analysis. Sociodemographic characteristics explained only 1.8% of the variance. Other complaints explained an additional 14.3% with psychosocial complaints being most influential. Knowledge of an underlying disease/problem explained an additional 9.9% of the variance. All of the characteristics together explained 26.0% of the attributions by the GPs. More psychosocially-attributed fatigue was found to correlate with consultations characterized by less physical examination, more diagnostic procedures to reassure, fewer diagnostic procedures to discover underlying pathology, more counselling, less medical treatment, less prescription and a longer duration than consultations with more somatically attributed fatigue. It is concluded that GPs do not discriminate between social groups when attributing fatigue to either somatic or psychosocial causes. The presence and character of other complaints and underlying diseases/problems, rather, relate to the GPs' somatic psychosocial attributions, which are then associated with particular aspects of the consultation.