The effects of varying times of cigarette deprivation on cognitive and performance tasks were examined. This study employed a between-subjects design in which five groups of smokers (9-10 subjects in each group) were compared on a vigilance task and cognitive measures as a function of length of deprivation (0, 2, 4, 8, or 24 hours). Each subject was tested during baseline ad-lib smoking and at one of the deprivation durations. Difference scores were compared between the 0-hour group and the 2-, 4-, 8-, and 24-hour groups. The results showed that there were no significant withdrawal effects on the measures at 2, 4, and 8 hours after cigarette deprivation with the exception of poorer performance on the Trail Making Test (B) at 4 hours, However, there were significant withdrawal effects at 24-hours deprivation. These included increased mean reaction time, increased variability in reaction time, and increased errors of commission on the vigilance task. There were near significant changes at 24-hours deprivation on the Trail Making Test (B) and Symbol Digits Modalities.