This study examined cigarette craving and blood nicotine levels in 11 male heavy smokers who were observed during 16 h of tobacco abstinence. Subjects rated their urge to smoke on a new brief 10-item questionnaire, Urge to Smoke (UTS), Schuh and Stitzer's four-item Visual Analog Scale (SSI), and a Strength of Urge to Smoke (SUTS) item. Testing occurred: 1) after 16 h (1700 h the night before to 0900 h the next morning) of abstinence from smoking; 2) after an ad lib smoking period following the 16 h abstinence; 3) every hour during 6 hours of abstinence; 4) and finally, after the 6 h abstinence, another ad lib smoking period. Thus, subjects smoked twice in each session. Blood plasma nicotine levels were measured before, after, and every 2 h during the 6-h abstinence period for a total of six measures. Blood pressure and heart rate were measured prior to each blood draw. There was a significant negative correlation between blood nicotine levels and craving for cigarettes on all craving questionnaires (rs = -0.55 to -0.78; ps < 0.002). Carbon monoxide was shown to correlate highly with nicotine blood levels (rs = 0.83 to 0.98 across subjects; ps < 0.001). Results are consistent with the hypothesis that "urge to smoke" reflects nicotine seeking in continuing smokers.