Batterers with access to firearms present a serious lethal threat to their partners. The purpose of this exploratory study is to estimate the prevalence of and risk markers for gun possession among Massachusetts men enrolled in batterer intervention programs. The authors found that 1.8% of the men reported having a gun in or around their home. Those most likely to report having a gun were White, earned 25,000 US dollars or more per year, had served in the military, engaged in problem gambling, and had attempted homicide or threatened their partner with a firearm. Recommendations for strengthening relevant gun laws both within and outside of Massachusetts are discussed.