The existence and importance of excitement in gambling, the effects of runs of wins and losses on gambling behaviour and the relationships of both with sensation-seeking were investigated using samples of students and experienced gamblers in real and artificial gambling situations. Heart-rate increases, gambling behaviour and events such as ‘stake decision time’ were recorded as subjects played blackjack. Significant differences between real and artificial casinos were found for mean heart-rate increases over base-lines, for gambling behaviour and in the relationships between sensation-seeking, arousal and gambling in the two conditions. Doubt is cast on laboratory gambling as a valid analogue of the real gambling situation. Sensation-seeking and arousal are discussed briefly in relation to explanations of gambling.