Inclusion Criteria:  moderate to heavy cigarette smokers (10 cigarettes/day for > 1 yr; breath CO > 10 ppm) have been receiving methadone for at least three months attend at least weekly to receive methadone dose speak English have a telephone or access to a telephone are available over the next 6 weeks are interested in switching to either electronic cigarettes or nicotine replacement therapy  Exclusion Criteria:  use of ECs on > 2 of the past 30 days currently use medications that may reduce smoking (e.g., bupropion, varenicline, NRT) have unstable psychiatric conditions have near-daily or daily use of marijuana are pregnant had a cardiovascular event in the last month daily medication for asthma or COPD