Parkinson's disease (PD) is the second most common neurodegenerative disorder, affecting > 1% of the population aged “ 6† years, with its prevalence set to double by 20†0. In addition to its defining motor symptoms, PD involves a series of non-motor symptoms. cognitive impairment is an important non-motor symptom of PD, with a strong impact on patients, families and society. PD-associated cognitive decline (cD) can appear as early as the pre-motor stage of the disease, is heterogeneous in terms of clinical presentation and rate of progression. Although not always, CD evolves from subjective cognitive impairment (SCI), to minor cognitive impairment (MCI), and subsequently to Parkinson's disease dementia (PD-D). The incidence rate of D-BP is4-6 times higher than in healthy subjects of the same age, with a prevalence depending on the duration of the disease – over 83% in patients with a disease duration > 20 years. The impact of PD-D is related to increased mortality, overloading of caregivers and health systems. A number of risk factors for PD-D have been established, but are still being studied: clinical, neuroimaging, humoral, neuropathological. Pathophysiologically, neurotransmitter dysfunctions, lewy body, α-synuclein and ß-amyloid are involved. The assessment of PD-D implies neuropsychological testing of different cognitive domains, and the diagnosis is estab- lished according to the criteria of the Movement Disorders Society. The optimal management would be multidisciplinary, with the application of pharmacological and non-pharmacological strategies.