We present an update focusing on research from the past 2 years on cognitive impairment and dementia in basal ganglia disorders, including Huntington's disease, progressive supranuclear palsy, Parkinson's disease, Parkinson's disease dementia, and dementia with Lewy bodies. In addition to the many recent papers that aim to refine descriptions of the cognitive phenotypes in the basal ganglia disorders, the current literature addresses the use of cognitive assessment in differential diagnosis of clinically overlapping disorders, the effects of surgical and pharmacologic treatments on cognitive functions, and the relationship between cognitive impairment and functional disability. We also discuss opportunities for enhancing the understanding of cognition in basal ganglia disorders through the use of improved study design and assessment strategies.