Summary: A Public Health Seminar delivered by Melanie Pickett on Monday, April 26, 2010. The rate of acute myocardial infarction (AMI) deaths in Massachusetts was examined before and after the implementation of a comprehensive smoke-free workplace law in July 2004. The impact of the state law in cities/towns with and without prior local smoking bans and the effect of the local laws were examined for the period 1999 through 2006.