This research demonstrates the effectiveness of a brief daily self-applied optimism intervention in an adult normal population. Participants completed Life Orientation Test-Revised Positive and Negative Affect Scale Satisfaction with Life Scale and Burnout Measure scales before immediately after and one month after the intervention. At baseline optimism intervention group (N = 36) and control group (N = 41) were statistically similar on the variables of interest. At post-test and also one month later the intervention group demonstrated reduced pessimism negative affect and emotional exhaustion although optimism positive affect and life satisfaction did not increase. Higher initial optimism increased the intervention effect for the optimism group but not for the control group by diminishing negative affect and emotional exhaustion and increasing optimism. Sixty-one percent of the activities mentioned by the control group participants focused on duties and work compared to 28% in the optimism condition. No correlations were found between initial optimism or pessimism and the type of activities mentioned.