Objectives: Temporal stability of clinical-psychological questionnaires is problematic from a conceptual point of view, and it is empirically insuffi-ciently examined. In this paper we analyze the temporal stability of anxiety and depression, based on large samples. Methods: In three samples with N > 300 each (cancer patients, orthopaedic patients, and general population) the stability of anxiety and depression was assessed with the Hospital Anxiety and Depression Scale (HADS). Results: The stability coefficients range from 0.60 to 0.75. They are highest in the sample of the orthopaedic patients with a time interval of only three weeks between the examinations. The temporal stability of anxiety and depression in females is as high as that of males. Individual change scores of anxiety and depression are correlated with about 0.50. Conclusions: The coefficients which are usually adopted in the measurement of change are not suited to describe temporal stability. Further research with sufficiently large samples is needed to unravel the conditions which determine the stability.