The central hypothesis of this article, that large by fathers in childrearing are associated with high stability, is tested against two competing hypotheses about stability. The hypotheses are examined using data from a national survey of households in the Netherlands. Investments are measured with retrospective questions about the degree to which fathers were involved in childrearing tasks. Divorce is measured indirectly, with questions about husbands' and wives' perceptions of the stability of their marriage. Multivariate analyses indicate that when fathers are more involved in childrearing, they have a stabler marriage. When indicators of the wife's satisfaction are included, however, the effect of the father's involvement disappears. Involved fathers have stabler marriages, not because they have much investment to lose after a possible breakup, but because the wife is happier if the husband is strongly involved with the children. One of the better-documented findings in the divorce literature is that couples with children are less likely to divorce than childless couples. The between stability and number of children has been documented with vital statistics early in this century (Van Zanten & Van den Brink, 1938) and has been confirmed in sophisticated multivariate analyses of large-scale survey data (Booth, Johnson, White, & Edwards, 1984; Heaton, 1990; Morgan, Lyle, & Condran, 1988; Waite & Lillard, 1991). Recent American analyses indicate that, after controlling for the duration of marriage, age at marriage, and educational attainment, the divorce rate for childless couples is almost 40% higher than for couples with one child and is about 60% higher than for couples with two children (Heaton, 1990). Similar differences are observed in other modern industrial societies, such as Germany (Diekmann & Klein, 1991) and the Netherlands (Manting, 1994). A common interpretation of the association between children and divorce is that children function as marital (Becker, Landes, & Michael, 1977). According to this theoretical perspective, people produce a set of goods in a that are more valuable inside than outside the relationship. The production of such goods can be seen as investments [that] increase commitment and help lock the individual into his or her relationship (Rusbult, 1983, p. 103; see also Weesie & Raub, 1995). Examples of relation-specific are a common circle of friends, knowledge of each other's personal traits, and the accumulation of shared life experiences. In relationships, children are probably the best example of such because both spouses have more to lose after a divorce when they have children. Divorced women with children have more difficulty entering the labor market than childless women and, consequently. experience a greater decline in economic well-being (Smock, 1994). Divorced women with children are also less likely to remarry, which further limits the chances of improving their living standard after divorce (Smock, 1990). The costs of divorce for men are primarily psychological and social. In most breakups, mothers get custody of the children. Fathers see their children infrequently after a divorce, and the contacts they maintain with them are less intense and of lower quality (Furstenberg & Cherlin, 1991). In short, the expected costs of divorce are higher when couples have children. The high cost of divorce may not prevent marriages from breaking up, but it clearly provides both men and women incentives to work out problems and, in doing this, reduces the likelihood of divorce. Although the notion of capital is a plausible interpretation of the between divorce and number of children, it is not the only one. Some have argued that couples stay together not because they, themselves, have more to lose, but because they think a divorce would hurt their children. …