Drug overdose deaths in the United States have more than doubled since 1999. During 2013, 43,982 drug overdose deaths (unintentional, intentional [suicide or homicide], or undetermined intent) were reported. Among these, 16,235 (37%) were associated with prescription opioid analgesics (e.g., oxycodone and hydrocodone) and 8,257 (19%) with heroin. For many years, community-based programs have offered opioid overdose prevention services to laypersons who might witness an overdose, including persons who use drugs, their families and friends, and service providers. Since 1996, an increasing number of programs provide laypersons with training and kits containing the opioid antagonist naloxone hydrochloride (naloxone) to reverse the potentially fatal respiratory depression caused by heroin and other opioids. In July 2014, the Harm Reduction Coalition (HRC), a national advocacy and capacity-building organization, surveyed 140 managers of organizations in the United States known to provide naloxone kits to laypersons. Managers at 136 organizations completed the survey, reporting on the amount of naloxone distributed, overdose reversals by bystanders, and other program data for 644 sites that were providing naloxone kits to laypersons as of June 2014. From 1996 through June 2014, surveyed organizations provided naloxone kits to 152,283 laypersons and received reports of 26,463 overdose reversals. Providing opioid overdose training and naloxone kits to laypersons who might witness an opioid overdose can help reduce opioid overdose mortality.