Addenbrooke’s Cognitive Examination III (ACE-III) is an extended cognitive screening instrument for an early detection of cognitive impairment, initial differential diagnosis of dementia syndromes and monitoring of disease progression. ACE-III assesses attention and orientation, memory, verbal fluency, language and visuospatial function. The scale may be used by physicians and psychologists as either a stand-alone cognitive screening or an introduction to a more in-depth neuropsychological assessment. It comprises a shorter scale, Mini-ACE, which can also be used independently as a very short screening. In this paper, the ACE-III was compared with other most common cognitive screening tools, such as the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA). We have presented the clinical utility of ACE-III profile analysis in the differential diagnosis of selected neurodegenerative diseases. We have reviewed ACE-III profiles typical for late and early onset Alzheimer’s disease, frontotemporal lobar degeneration syndromes, Parkinson’s disease and atypical parkinsonian syndromes as well as vascular dementia. Among Alzheimer’s disease atypical variants, posterior cortical atrophy, logopenic variant of primary progressive aphasia and frontal variant have been discussed. As regards the frontotemporal lobar degeneration spectrum, the behavioural variant of frontotemporal dementia, non-fluent and semantic variants of primary progressive aphasia have been presented. Finally, among parkinsonism plus syndromes, dementia with Lewy bodies, multiple system atrophy, progressive supranuclear palsy and corticobasal degeneration have been reviewed.