Hepatic encephalopathy (HE) is a complex neuropsychiatric syndrome that exhibits a wide spectrum of nonspecific neurological impairments, ranging from subclinical alterations to coma and death. Minimal HE (MHE) is the initial stage of HE and is considered the greatest risk factor for its development. Patients with MHE show mild cognitive impairment, attention deficits, psychomotor slowing, and impaired motor coordination. These cognitive and motor alterations can lead to an increase in the risk of accidents and hospitalizations, which in turn reduce life quality and span. Therefore, MHE is a major health, social, and economic problem, whose diagnosis is essential for treatment and to prevent progression to HE. Currently, the MHE diagnosis is carried out mainly by psychometric tests, such as the Psychometric Hepatic Encephalopathy Score (PHES) and critical flicker frequency (CFF). Since the 11th World Congress of Gastroenterology (1998), PHES has been proposed as a gold standard for diagnosis of MHE. The spectrum of cognitive and motor impairments presented by patients with MHE is broad and cannot be assessed by PHES or CFF only. Other psychometric tests should be used to evaluate the full spectrum of cognitive and motor impairments, such as the Stroop test, the d2 test, the oral Symbol Digit Modalities Test, the digit span, letter-number sequencing test, bimanual coordination test, and visuo-motor coordination test. This chapter will detail the methodology necessary for performing psychometric tests used for MHE diagnosis, as well as other more sensitive tests for assessing associated cognitive and motor impairments.