Horse race and electronic gaming machine (EGM) gambling are popular forms of gambling, however the key motivational drivers to participation in these different forms are not clear. Gray (1982) and Gray & McNaughton (2000) Reward Sensitivity theory (RST) and Blaszczynski and Nower's (2002) cognitive behavioural pathways model of pathological gambling (PG) provide potential frameworks for examining these drivers. The aim of this study was to explore the relationships between gambling choice, gambling frequency and personality factors deriving from the models of Gray (sensitivity to reward, sensitivity to punishment), and Blaszczynski and Nower (sensation seeking, impulsivity, escapist motivation). The sample comprised 118 current gamblers who gambled twice or more per year on either horse racing or EGMs (77 male, 41 female, Mage 26.93 years). Horse race and EGM gamblers showed very different patterns of correlates. Horse race gambling frequency was independently predicted by male gender and sensitivity to reward, while the significant independent predictors of EGM gambling were escapist motivation and sensitivity to punishment. Results provide support for conceptualising frequent gamblers as a heterogeneous group with respect to their motivational drivers, with gambling preferences offering an important indicator of underlying motivations for gambling.