A cross-sectional study was made at Hospital de Clínicas de Porto Alegre, Brazil to detect depression in 299 non-psychiatric inpatients in 2002. This study was similar to another one made in 1987. In order to detect depression, PRIME-MD and Beck Depression Inventory were used. After discharge from the hospital, a survey was made in patient records set down by physicians and nurses looking for references on depression symptoms and/or diagnosis. The prevalence of depression was 34.6% (PRIME-MD) and 20.1% (BDI). A comparison between the data from 1987 and 2002 showed the same pattern of under-diagnosis. The paper presents considerations and alternatives to this same deficiency detected once again.