Cognitive styles are the lenses through which individuals habitually process information from their environment. In this study, we evaluated whether different cognitive style individual difference variables, such as explanatory style and dispositional optimism, could predict changes in affective state over time in community-dwelling older adults. Based on previous research, we hypothesized that an optimistic explanatory style would be adaptive except when combined with life stressors, but that dispositional optimism would predict positive affective states regardless of life events. We found that older adults with a more optimistic explanatory style for health/cognitive events actually appeared to develop more depressive symptoms over six months of follow-up. However, dispositional optimism and orientation toward the future predicted a better affective profile over time. (Contains 5 tables.)