Analysis of the extent to which husbands and wives agree in their attitudes toward a number of key issues that may affect fertility behavior shows that although aggregate views of men and women are remarkably similar, marital couples are frequently in disagreement, particularly if measures discounting for chance agreement of responses are employed. In other words, we cannot accept either the husband or the wife as a surrogate respondent. These conclusions are based on data from cross-sectional surveys in a developing society, Taiwan, of 2000 couples in which the wife was of childbearing age. The impact on fertility of such marital disagreement varies with the attitude in question. Followup birth data over a four-year period indicate that, when there is disagreement, it is the wife's attitude that has more influence on fertility, particularly if she has the stronger belief about the future security and status to be derived from a large family and from sons. In the constellation of factors that may affect fertility, increasing attention has focused recently on the role of the husband and his attitudes toward reproductive goals and toward values and The data for this paper were collected by the Taiwan Provincial Institute of Family Planning under the direction of T.S. Sun, in collaboration with the University of Michigan Population Studies Center and with the financial assistance of the Population Council. Grants from the Center for Population Research of the National Institute of Child Health and Human Development and the Ford Foundation provided support for the analysis. We wish to acknowledge the assistance of James B. Rogers in the computer work and of Ronald Freedman in comments on an earlier version of this paper.