This study has been designed to identify some of the factors that influence people to smoke, as well as the usefulness of these factors in predicting their smoking behaviour and their possible cessation. Specifically, the study focuses on the following research questions: (a) What are the motives that smokers themselves give to account for their smoking behaviour?; (b) are there sex differences in smoking motives?; and (c) how well do these motives account for any observed sex differences in tobacco consumption and the possible cessation of smoking? To identify smoking motives, a Smoking Inventory was developed. A sample of 80 current regular smokers (21 males, 59 females) from the Darwin metropolitan area wrote down as many reasons as they could think of to account for their own smoking behaviour. Content analysis of these responses resulted in 25 reasons for smoking. In order to answer the study's research questions, 128 regular smokers (59 males, 69 females) were surveyed as to their endorsement of the 25 smoking reasons, their daily cigarette consumption rate, their perceived likelihood, difficulty, and confidence in giving up smoking, and the perceived health risks associated with smoking. Factor analysis of the respondents' endorsement of the 25 smoking reasons yielded four distinct motives for smoking—Social Acceptance, Addiction/ Habitual Needs, Pleasure, and Boredom. Multiple regression analysis indicated that, of the four motives Addiction/Habitual Needs and Pleasure were found to be strongly endorsed by the respondents as major reasons for their smoking. The Social Acceptance and Boredom motives were found to be unimportant reasons. Analysis yielded no significant sex difference for any of these motives, indicating that male and female respondents in this study smoke for similar reasons. For both male and female smokers, the best predictor of their consumption rate and perceived difficulty and confidence in giving up was the Addiction motive. In addition, smoking for pleasure was found to be negatively related to smoking cessation, but for male smokers only. The results also suggest that male smokers may find it easier to quit than female smokers if they smoke primarily for social reasons. The implications of these findings to smoking treatment programs are discussed.