A non-problematic gambler: gambles for pleasure, according to his/her financial status, accepts to lose money bet, and never gambles to chase losses. ― Specific features to Gambling Disorder (GD) are gambler's fallacy and other cognitive biases applied to random conditions related to money incentives, such as chasing, illusion of control and near miss effect. ― Problem gamblers rarely seek treatment despite of negative consequences and suffering, assessment in primary care settings is accordingly of major importance. ― Treatment of GD consists principally in psychotherapy targeting gambler's fallacies and in debt management.