Although information about marital disagreements is included in most scales of marital quality, disagreements have generally not been studied as outcomes of importance in their own right. This is unfortunate in light of recent research documenting that marital disagreements have a powerful effect on mental health over and above the effects of marital quality. In this report, we describe a prospective analysis of the frequency and determinants of marital disagreements aimed at taking a first step toward treating disagreements as important in their own right. The analysis is based on a two-wave community survey of married couples that obtained basic descriptive information about both the frequency of marital disagreements and a variety of social and personal characteristics that might be their determinants. Results show that nearly all respondents report having marital disagreements at least some of the time, with the vast majority reporting average frequencies between one and two disagreements per month. Prospective analyses of daily diaries obtained from a random subsample of the survey respondents confirmed the accuracy of these retrospective frequency estimates. Multiple regression analyses revealed that personality and social support are the most powerful predictors of disagreement frequency. We close with a discussion of the implications of these results for future research on marital disagreements.