Bidis, hand-rolled cigarettes imported from India, have become increasingly popular among US teenagers. These cigarettes are perceived as a safer, more natural alternative to conventional cigarette smoking. The present study was conducted to determine whether the acute effects of bidis and conventional cigarettes are similar. Undergraduate cigarette smokers with a history of bidi smoking were tested in two experimental sessions, using a within-subject design. Subjects smoked both a bidi and a conventional cigarette. Physiological and biochemical measures, subjective evaluations, and smoking behavior characteristics were obtained before, during, and after smoking each experimental cigarette. Although time to smoke and puffs per cigarette were significantly higher after the bidi, physiological and biochemical effects of bidi smoking were similar to those of smoking conventional cigarettes. Bidis were rated less satisfying than the conventional cigarette. However, there were no significant differences between the cigarettes in other subjective measures. Our results do not support the belief that bidis are a safe alternative to conventional cigarettes. Furthermore, bidi smoking, like conventional cigarette smoking, may lead to nicotine dependence.