This paper outlines a system dynamics model that has been developed to assist the Ministry of Health to evaluate the dynamic consequences of tobacco control policies in New Zealand. The model consists of 4 sectors: population; smoking prevalences; second hand smoke; and tobacco attributable deaths.  The model is simulated for 20-30 years into the future. The simulation package used is 'iThink', and a user interface is presented for policy analysis. A range of illustrative scenarios are provided, including: business as usual; fiscal strategies involving less affordable cigarettes; harm minimisation strategies involving either less addictive cigarettes or less toxic cigarettes; and combinations of the above policies.  The main output variables (performance measures) include current smoking prevalence, tobacco consumption, and tobacco attibutable mortality. Finally some concluding comments are provided and areas for future model enhancement are identified.