While it is consensus that minimal hepatic encephalopathy (mHE) has significant impact on a patient's daily living, and thus should be diagnosed and treated, there is no consensus about the optimal diagnostic tools. At present the most frequently used psychometric methods for diagnosing minimal hepatic encephalopathy are the Inhibitory Control Test and the Psychometric Hepatic Encephalopathy Score PHES. Another frequently used method is Critical Flicker Frequency. The PHES and the Repeatable Battery for the Assessment of Neuropsychological Status have been recommended for diagnosing mHE by a working party commissioned by the International Society for Hepatic Encephalopathy and Nitrogen Metabolism. Recently the Continuous Reaction Time Test, which has been used in the 1980ies, has gained new interest. Today, no data are available that allow to decide which of these methods is the most appropriate. In fact, even basic information such as dependence on age, sex and education or influence of diseases that frequently accompany liver cirrhosis upon test results is missing for most of them. Future studies must address these questions to improve diagnosis of mHE.