Objective: To determine the prevalence and types of dementia in a Lima’s urban community. Design: Bietapic conglomerate sampling. Setting: Private health institutions. Patients: Older than 65 years subjects. Interventions: In the Cercado de Lima district, 1 532 older than 65 years subjects randomly selected had brief neuropsychological evaluations including the Mini Mental State Examination (MMSE), drawing the Clock Test (PDR), and Pfeffer’s functional activities questionnaire (PFAQ). According to the results obtained, individuals were classified as selected or not selected. The group selected included those subjects presenting/displaying cognitive deterioration, who further had neurological and neuropsychological evaluations, laboratory tests and brain computed tomography (TC). Main outcome measures: Dementia prevalence. Results: We found 105 cases of dementia corresponding to 6,95%...