Nicotine replacement therapy (NRT) is recommended for tobacco cessation on the basis of pharmaceutical industry research showing its effectiveness when combined with counseling. The tobacco industry opposed NRT when it first appeared in the 1980s but by 2016 was marketing its own NRT products. We used internal tobacco industry documents dated 1960 through 2010 to identify the industry's perceptions of NRT. As early as the 1950s, tobacco companies developed nonsmoked nicotine replacements for cigarettes, but they stopped out of concern that marketing such products would trigger Food and Drug Administration regulation of cigarettes. In the 1990s, after pharmaceutical companies began selling prescription NRT, tobacco companies found that many smokers used NRT to supplement smoking rather than to quit. In 2009, once the Food and Drug Administration began regulating tobacco, tobacco companies restarted their plans to capture the nicotine market. Although the tobacco industry initially viewed NRT as a threat, it found that smokers often combined NRT with smoking rather than using it as a replacement and began marketing their own NRT products.