Studies of the effect of negative experiences on mood have shown an association between negative events and mood reported on the same day. In trying to make a more convincing case that negative events cause shifts in mood, we examined the effects of naturally occurring, daily events on next-day mood. From a sample of 50 men who had reported events and mood prospectively, 17 whose reports included a severe, negative event were selected. Same-day and next-day associations were examined using both self-reports from the men and wives' reports about their husbands' mood. Same-day associations were observed, but there was no strong evidence of changes in next-day mood. The results offer no support for 2-day or longer effects of daily, negative events and highlight the need for prospective studies for addressing causal questions and for cognitive mediational variables, such as coping, to be included in future studies.