A system dynamics computer simulation model of New York States impaired driving system Rod MacDonald Abstract Drinking and driving continues to be a problem that plagues the U.S. Last year there were just under 12 thousand people killed in alcohol related crashes in the United States. In New York State, in 2007, there were 373 people killed in alcohol related crashes. In order to address this problem the NYS Legislature passed stricter drunk driving laws aimed at those considered hard-core drunk drivers, i.e. drivers with high blood alcohol content (BAC above .18). In order to gain an understanding about the implications of this new law, before it went fully into effect, the NYS Governor’s Traffic Safety Committee commissioned the development of a system dynamics computer simulation model to examine the implications of this new law. The talk will examine the process of model development, acceptance and use.