The purpose of this study is to assess the effect of the Helpers Stay Quit training on abstinence over time of newly abstinent smokers, and on the interactions they have with their personal network related to smoking and smoking cessation.

Despite major gains in smoking cessation treatment, over half of recently quit smokers will relapse within the first year. To date, relapse prevention interventions have focused on the newly abstinent smoker ("abstainer"), and not attempted to directly or indirectly influence the abstainer's personal network, e.g. by helping the abstainer influence others in their personal network to quit. Personal networks exert powerful effects on initiating and maintaining smoking behavior, and can facilitate maintaining abstinence or trigger relapse. A "help others" intervention that seeks to increase the abstainer's ability to influence smokers in their personal network to quit - thereby creating a social environment more supportive of long-term abstinence - may have a beneficial effect on relapse. The Helpers Stay Quit intervention encourages abstainers to reinforce their own abstinence through helping others quit, and to proactively influence their personal network to be more conducive to long-term smoking abstinence. Helpers Stay Quit teaches abstainers how to encourage other tobacco users to quit and avoid relapse through a non-confrontational "helping conversation" that encourages quitting and use of evidence-based cessation aids (e.g. Quitlines, cessation medications) without confrontation and nagging. The investigator hypothesizes that Quitline abstainers exposed to Helpers Stay Quit will have higher 30-day and 7-day point prevalence abstinence than those receiving Quitline follow-up usual care, and that the effect of Helpers Stay Quit may be mediated by personal network characteristics. To test this hypothesis, the investigator proposes a pragmatic randomized controlled trial with embedded mixed-methods personal network study to assess the effect of Helpers Stay Quit training on proportion and duration of abstainers' abstinence over time, and on abstainer's personal network interactions related to smoking and smoking cessation. Metrics derived from the personal network study will be used for mediational analyses of overall, and gender-based effects of Helpers Stay Quit on smoking relapse.

Inclusion Criteria:

• 18 years or older
• Abstinent from smoking for between 14 and 60 days
• Primary tobacco use is cigarettes
• Has access to Internet via computer or mobile device
• Self-described proficiency with English
• Willing and able to send/receive weekly text messages using personal mobile phone plan
• Will allow Quitline to share their client data with research team
• Willing to complete online surveys at baseline, 3-, 6-, 9- and 12 months
• Willing to self-collect dried blood spot and send back to research team
• If assigned to Helpers Stay Quit condition, willing to complete training within 14 days
• If selected, willing to participate in qualitative interview
• Willing to forego any other training for tobacco cessation intervention/support (i.e., to become a cessation counselor/facilitator or support person, e.g., 'quit buddy') for the duration of their study enrollment

Exclusion Criteria:

• Any prior exposure to Helpers training or other cessation training in the previous 2 years

Statistician analyzing outcomes is blinded to study arm assignment