Of 41 couples, 20 were classified as "stably aggressive" while 21 who did not indicate interspousal aggression were included for comparison. During the assessment phase of the study, each couple engaged in a 10-minute problem-solving discussion based on an issue about which they disagreed. Adjectives describing affective states were selected from the circumplex affect model generated by Watson and Tellegen (1985), and each affect was rated 24 times for each couple. Study results implicated the expression of negative affect as a powerful longitudinal predictor of spousal aggression. Aggressive and nonaggressive couples did not differ in terms of their degree of arousal during discussions, implying that the hedonic tone of discussions was the factor associated with subsequent aggression. Further study is recommended to explore the structure of interpersonal exchanges of affect in couples with varying lengths of marriage, levels of satisfaction, and histories of aggression and conflict. 18 references, 4 tables, 1 figure.