Participants in this open-label study will be randomly assigned to one of three treatment conditions: switching to an ST brand with less concentrated nicotine and controlling for ST use; switching to an ST brand with less concentrated nicotine, combined with no limit on ST intake; or continued use of usual ST brand with no limit on intake (control group). Participants in both brand-switching conditions will use ST brands that have 50% less nicotine than their usual ST brands for the first 4 weeks. For the next 4 weeks, participants in the brand-switching conditions will use ST brands that have 75% less nicotine that their usual ST brands. Study visits will ocur once weekly during the 8-week treatment period. The number of participants who do not complete treatment, reduce nicotine intake, or quit completely will be assessed at Week 8 and at follow-up visits, which will be held 12 and 26 weeks following the completion of treatment.