Unintended pregnancy is a widespread problem in the United States. The ill consequences of unintended pregnancy on children, women, and families have been widely documented, but scant information exists on the demography and consequences of unintended pregnancy among men. The primary objectives of the proposed research are: (1) to document the extent and patterns of unintended fertility among men; (2) to examine the effect on marriage and relationship dissolution of having an unintended birth relative to the consequences of having an intended birth, a birth which was neither intended nor unintended, and having no birth during the same observation period; and (3) to examine the consequences of having an unintended birth on the psychosocial well being of the father, relative to the consequences of having an intended birth, a birth which was neither intended nor unintended, or having no birth during the same observation period. Data from the 1982-1998 rounds of the National Longitudinal Surveys of Youth (NLSY), and the 1994-1998 rounds of NLSY-YA will be used. These are the only large-scale national data sets that have the information we need to achieve our analytical objectives. The investigation of the effects of unintended fertility on marriage and relationship dissolution, is guided by a conceptual framework based on a utilitarian perspective that is central to the macroeconomic theories of the family, marriage, and fertility, the rational choice theory, and the exchange theory. Briefly, according to this perspective, human beings are motivated out of self-interest, and individuals account for the costs and benefits of their actions and make choices that maximize their utility. When unexpected events occur (e.g., a birth), the anticipated utility diminishes, and individuals resort to coping mechanisms to deal with the stress caused by the unexpected event, or abandon the relationship, or the marriage. In addition to relationship dissolution, we posit that there are other psychosocial consequences of a birth, and that these consequences vary by the intended status of the pregnancy outcome. The specific psychosocial well being outcomes of interest are alcohol and drug use, and depressive symptoms for the adult NLSY sample. Three additional well being outcomes that will be examined for the Young Adult sample are marital harmony, self-esteem, and mastery (i.e., self- efficacy). We also posit that the effect of intended of births on relationship dissolution and well being outcomes will vary by the type of relationship (i.e., interaction effects).