This thesis details a continuing body of research investigating the contribution of personality to disordered eating and alcohol abuse in young women. There is growing evidence of high levels of reward sensitivity in women with both disorders, and high levels of punishment sensitivity in dysfunctional eating women. However, it is unlikely that personality alone accounts for the development of such dysfunctional behaviour. Two studies were conducted to further examine the contribution of reward and punishment sensitivity to these disorders. In the first study, 443 university women completed self-report measures of alcohol use, dysfunctional eating, reinforcement sensitivity, parental drinking, family environment and maternal eating. Reward and punishment sensitivity were better predictors of disordered behaviour than family factors, although maternal dysfunctional eating significantly increased the risk of daughters' dysfunctional eating. Punishment sensitive daughters of bulimic mothers reported the highest level of bulimic symptoms themselves. Punishment sensitivity also functioned as a partial pathway variable between family risk and disordered eating. Given the stronger contribution of personality to disordered behaviour, a second study was conducted in which 131 women completed behavioural tasks under conditions of reward and punishment. Performance on a computerised measure of punishment sensitivity was associated with greater levels of dysfunctional eating but not drinking. However, performance on a card-sorting task of reward sensitivity failed to correlate with self-reported reward sensitivity or disordered behaviour. It was concluded that an innate sensitivity to reward increases the risk of disorders characterised by strong approach tendencies, whilst high punishment sensitivity, perhaps due to a chaotic family, increases the risk of dysfunctional eating, particularly daughters of eating disordered mothers.