The study is in the field of psychogerontology/psychogeriatrics, but it is in touch also with a range of humanitarian sciences. The study on the self-evaluations, values and mental health has been cross-sectional and longitudinal. 708 persons (341 men and 267 women) aged 70 to 98 years, constituting a 20% random sample of the population 70 and over from 45 villages near Sofia have been studied in 1971–1972. A test of self-evaluation of the personality and its social coherence is used along with nine psychological cognitive tests, an interview and a comprehensive medical and psychiatric examination. The group studied is homogeneous in ethnic, social-cultural and migration respect. In addition to the cross-sectional appraisal, a longitudinal assessment has been performed in intervals of 3, 5, 10, and maximum 16 years. Finally, an attempt of time-lag examination of old people 70 and over from two of the previous 45 villages is performed in 2008, i.e. 36 years after the initial study – in different social and political conditions.