Electronic Cigarettes as a Harm Reduction Strategy in Individuals With Substance Use Disorder

Inclusion Criteria: * smokes at least 10 cigarettes per day * meet DSM-V AUD and/or OUD within the past year, interested in reducing CPDs * able to provide consent * use a cell phone, are willing/able to receive and respond to daily text messages regarding their cigarette use and e-cigarette use on their cell phone * provide one additional contact, and are willing to use an e-cigarette for 3 weeks. Exclusion Criteria: * pregnant and/or breast feeding (self-reported) * currently using smoking cessation medications (including other forms of NRT, buproprion, or varenicline) * enrolled in a smoking cessation program or another cessation tria * have used an e-cigarette in the past 14 days * have used any other tobacco products (pipe, cigar, cigarillos, snuff, chewing tobacco, rolling tobacco, or hookah/shisha) in the past 30 days * report having a history of asthma, other airways diseases, or heart disease.