Receiving support in committed relationships has frequently been associated with negative psychological outcomes in the recipient, such as increased distress. The authors hypothesized that these negative effects could be offset by support recipients' reciprocation of support, that is, by creating a sense of supportive equity. To investigate this hypothesis, the authors obtained daily reports of mood and of received and given emotional support from both partners in 85 couples throughout a 4-week period. Reciprocity in support transactions was associated with higher levels of positive mood and lower levels of negative mood. In line with previous research, receiving support without reciprocation was associated with increases in negative mood. Giving support, regardless of receipt, was associated with a decrease in negative mood.