Effects of chain-smoking, a 15-h smoking abstinence, and the nicotine yield of cigarettes on puff indices were studied in eight healthy smokers by using a controlled crossover study design. Puff parameters were measured puff by puff with a portable measuring device when 10 or 20 cigarettes, with nicotine yields of 0.3 and 1.0 mg, were smoked per day. The interval between sessions was 1 h, and the 20 cigarettes per day were chain-smoked 2 at a time. Serum cotinine indicated that smokers compensate completely for the lower nicotine delivery from the 0.3-mg cigarette. Smokers almost doubled total puff volume per cigarette and per day mainly by taking more puffs from the low-nicotine cigarettes and slightly prolonging puff duration. However, nicotine deprivation and chain-smoking had a relatively minor effect on puffing indices with both brands, a fact that agrees poorly with the nicotine titration hypothesis. However, in the course of every single cigarette of the day smokers significantly reduced puff duration and puff volume toward the end of the cigarette, which probably involves satiation of the nicotine crave but may also be due to changes in taste of the smoke.