Lacunar infarcts or lacunes result from occlusion of a single penetrating artery and account for approximately a quarter of cerebral infarctions. The short-term prognosis of symptomatic lacunar infarct is favorable - that is, low early mortality and a high proportion of symptom-free patients at hospital discharge - but the prognosis in the mid- and long-term is less favorable as there is an increased risk of death, recurrence of stroke and vascular-type dementia. This unfavorable prognosis is mostly related to asymptomatic progression of small-vessel disease. Therefore, the consideration of lacunar infarct as a relatively benign disorder is misleading. Whereas the clinical relevance of lacunar infarct to lacunar syndromes is widely accepted, the degree to which lacunes affect cognitive function remains unclear. The reviewed article presents new data from the multinational Leukoaraiosis and Disability (LADIS) study, which shows that an increase in silent lacunes parallels significantly with longitudinal cognitive decline in executive functions and psychomotor speed. The study is discussed in the context of the current state and knowledge regarding cognitive impairment in ischemic cerebral small-vessel disease, in particular regarding its health consequences.