Neuropsychological testing (NPT) needs to be reserved for patients requiring particularly detailed testing when the symptoms are covert and subtle or where deficits need more precise cognitive appraisal. This applies especially to those with subjective complaints (so- called “worried well”), where close monitoring of cognitive deficits over time is required as with rehabilitation interventions or studies and medicolegal-related assessments. NPT is constrained principally by testing duration and availability. It should also be noted that acute and subacute neurological patients in a tertiary medical setting are often not amenable to NPT as they have obvious significant impairments such as delirium, encephalopathy, global aphasia, severe neglect syndromes or anosognosias, and many common stroke syndromes. In dementia, basic screening is possible, but with mild cognitive impairment, NPT is often indicated. Multiple sclerosis is a good example where elementary neurological deficits such as ophthalmoparesis, ataxia, and sensorimotor impairments may overshadow the majority of patients who have altered cognitive as well as behavioral deficits. Neurotoxicological exposure manifests with executive dysfunction and malingering are very good examples of where NPT may play a pivotal role in diagnosis.