The Iowa Gambling Task is a behavioral measurement which was developed to examine decision-making based on the Somatic Marker Hypothesis. Participants have to make series of choices altogether 100 times from four decks of cards. The decks have different characteristics with regards to gains and losses. After the initial analyses - with a focus on patients with damage to the ventromedial prefrontal cortex - the tool soon became one of the most frequently used technique of measuring hot executive functions. It is also used to measure impulsivity. Structures involved in decision-making constitute the neural basis of the Task. IGT is applied in several different disorders (in connection with decision-making and impulsivity as well). In recent years different versions have been developed, and these modifications may have different effects on IGT performance, and may also influence what the Task measures exactly. With growing empirical evidence several questions have arisen in connection with the composition of the decks (gain-loss magnitude vs. frequency, prominent deck B phenomenon) which suggest to use other indexes as well besides the net scores.