Decision-making is a higher-order brain function that consists in choosing between behaviors/options. Basal ganglia (BG) dysfunction is known to be involved in decision-making deficits observed in patients suffering from BG-related disorders including neurological (e.g., Parkinson's disease) and psychiatric (e.g., obsessive compulsive disorders) disorders. However, the neural mechanisms and computations of decision-making in BG network are elusive and do not satisfactorily reflect the complex and known BG anatomy and physiology. Moreover, there are different types of value-related information (i.e., outcome value, action value, chosen value and choice only) the BG neurons encode which are required during value-based decision-making. To tackle these issues, we trained two rhesus monkeys in a task where they had to choose by performing arm reaching movements between two lotteries that probabilistically predicted different quantities of gains or losses of the same reward. Then, we performed multi-site and multi-electrode in vivo electrophysiological recordings (32 recording channels) within key ventral and dorsal areas of the BG network (i.e., ventral striatum and ventral pallidum vs. caudate nucleus and external globus pallidus) of the monkeys while they were engaged in the behavioral task. In doing so, we characterized distinct task-dependent activities related to the estimation and evaluation of the consequences/outcomes of the choices in the ventral areas and to the preparation and execution of these choices in the dorsal areas. This dichotomic function of the BG ventral and dorsal circuits is therefore likely to be critical to the implementation of BG physiology and pathophysiology.