The objectives of this study were to determine the prevalence of smoking, identify the effects of deployment on smoking behavior and risk factors for smoking, and determine the short-term health outcomes associated with smoking in Australian Defence Force (ADF) personnel. Participants were randomly sampled from ADF members who deployed to the Solomon Islands between 2003 and 2005 and from a nondeployed comparison group. In total, 435 of 995 (44%) eligible individuals completed the study questionnaires. The prevalence of current smoking was highest in those who had completed less formal education and those who served in the Navy. Nearly two-thirds (63%) of current or former smokers smoked more while on overseas deployment. Current smokers were more likely to report current wheeze, shortness of breath, and persistent cough compared with nonsmokers. The ADF should continue to address cigarette smoking through its health promotion and health review programs and implement activities to reduce cigarette smoking on deployment.