The article provides a review of current literature on the diagnosis and treatment of mild cognitive impairment (MCI). MCI is not a common outcome of brain aging; it is an intermediate state between normal cognitive status and mild dementia. The MCI concept has been actively developing over the past few decades, a lot of knowledge and clinical experience has been accumulated, and numerous clinical trials are being conducted to develop effective methods of diagnosis and therapy. Treatment of pre-dementia cognitive disorders differs in many ways from therapy for dementia and has a better prognosis, therefore, it is recommended to diagnose and begin treating cognitive disorders as early as possible. The main possibilities of drug and non-drug therapy are described, with an emphasis on the use of the dopamine receptor agonist piribedil in the treatment of MCI and sensory deficit in elderly patients. The mechanisms of action of the drug are analyzed, data from the main clinical studies of the efficacy and safety of piribedil are presented: the positive effect of the drug on cognitive functions has been shown in more than 10 international clinical trials including about 7000 patients and in a number of post-marketing works performed on the Russian population of patients. Piribedil is successfully used for various types of cognitive disorders, both neurodegenerative and vascular, of mild to moderate severity.