Consistent with the finding of other studies of this type, harm elimination following long bouts of forced abstinence was common in our study. Our data are very similar to those from an analysis of the 2002 and 2003 Tobacco Use Supplement to the Current Population Survey(TUS-CPS). In both our study and the TUS-CPS,(1)quitting rates were lower for cigarette smoking than for smokeless tobacco use at the 1-year follow-up,(2) exclusive cigarette use was a more stable pattern of tobacco use than were smokeless tobacco use or dual use, (3) switching from one type of tobacco use than were smokeless tobacco use or dual use, (3) switching from one type of tobacco use to another was infrequent and was more likely to be from cigarettes to smokeless tobacco , and (4) harm reduction ( I.e., from smoking or dual use to smokeless tobacco only ) was much less common than was harm escalation ( I.e., from smoking or smokeless tobacco only use to dual use ). Our finding that dual users the most likely of the groups to switch tobacco use patterns and the least likely to report nonuse at follow-up was also consistent with previous studies. Considered together , these data would suggest that in the United States , harm escalation may lower the probability of becoming tobacco abstinent if smokers become dual users. This escalation is a possible unintended consequence of promoting smokeless tobacco as a harm reduction strategy for smoker.