Symptoms of depression have been associated with increased smoking prevalence and failure to quit smoking in several cross-sectional and population-based studies. Few studies, however, have prospectively examined the ability of current symptoms of depression to predict failure to quit smoking in treatment-motivated smokers. Pretreatment depressed mood was assessed by 3 different methods in 3 separate samples, 2 of which comprised smokers receiving combined pharmacological and behavioral treatments and a 3rd in which smokers received self-help materials only. In all studies, time in days from quit day until the 1st cigarette was ascertained to document survival. Survival analyses showed that in all 3 studies survival time was significantly and negatively related to measures of even very low levels of pretreatment depressed mood. Results were replicated across 3 independent samples and were robust and uniformly clear, indicating that low levels of depressive symptoms assessed at baseline predict time to 1st cigarette smoked after attempted quitting.