The main problem of depression is not only the high prevalence of the disorder but also its serious consequences on the patient's quality of life and the associated social costs in terms of health care resource utilization and productivity losses. In recent years, there has been a considerable improvement in the knowledge of depression from the pathogenic, clinical and therapeutic perspectives. The present study analyzes whether such advances are reflected in a positive evolution of the treatment of depression in Spain. To this effect we have contrasted the results of two socio-sanitary studies published in this country: the White Book editions of 1982 and 1997 (WB82 and WB97, respectively). From the methodological perspective, the physician selection criteria employed were very uniform (structured questionnaires delivered to 128 (WB82) and 300 (WB97) randomly selected psychiatrists). The origin of patients consulting for specialized care has varied over this 15-year period. In effect, WB82 patients were essentially referred by friends (87.5%) and from the primary care setting (44.5%), whereas in the WB97 study referral from primary care predominated (50.1%), followed by the patient's personal decision (24.8%). In turn, 40.7% and 51.7% of the psychiatrists in WB97 respectively considered the diagnostic and therapeutic means available in primary care to be insufficient. The priorities for improving patient quality of life, as reflected by both editions of the study, were the training of primary care physicians and the adequate provision of means in the mental health care centers. On the other hand, fewer problems for establishing a correct diagnosis were referred in the 1997 edition of the study (28.7%) than in 1982 (48.4%). In this sense, the main problem reported in WB82 was the lack of specialized training, whereas the masking of depression by some other disease process or symptoms was the main problem in WB97 (67.6% vs 21.1% according to WB82). The main symptoms upon which the diagnosis of depression are based do not seem to have evolved much in the past 15 years. The most frequently cited manifestations were a worsening of mood, loss of interest and leisure capacity, sleep alterations and diminished vitality. A comparative analysis of the therapeutic resources used was not possible, for prior to 1982 the only drugs available to physicians were the classical tricyclic agents and some MAO inhibitors; the selective serotonin reuptake inhibitors (SSRIs) - possibly the greatest advance in the treatment of depression in these 15 years - had not yet been introduced. Nevertheless, it should be pointed out that 98% of the psychiatrists consulted in WB97 considered pharmacologic treatment to be the most widely adopted form of management once depression has been diagnosed.