The primary aim of this study was to investigate the complex relationship between personality, smoking outcome expectancies and smoking behaviour. A secondary focus was the role of nicotine dependence in smoking. Students from a 1st year Psychology course and additional participants recruited using a snowballing technique (N=151) completed a questionnaire assessing the Big Five personality dimensions Neuroticism(N), Extraversion(E), Openness (O) Conscientiousness (C), Agreeableness (A), smoking outcome expectancies, nicotine dependence and smoking behaviour. It was predicted that the relationship between N, and E and smoking behaviour would be mediated by the expectancies of Negative Affect Reduction and Stimulation-State Enhancement respectively. It was found that the traits of N and E did not relate to smoking behaviour. Subsequently, the mediational hypothesis was not supported. As predicted, however, the expectancy of Negative Affect Reduction related to smoking behaviour, although the expectancy Stimulation-State Enhancement was not. This study also explored whether C moderated the relationship between the expectancy of Health Risks and smoking behaviour. Results did not support this notion. As expected, nicotine dependence was related to smoking, which was unaffected by the inclusion of non-smokers in post hoc analysis. Unexpectedly, this study found that people low on A tended to smoke more. Findings were interpreted relative to cultural change in perceptions on smoking. Results have implications for smoking prevention and cessation programs.