Carolyn Pape Cowan and Philip A. Cowan University of California Berkeley Changing Families: A Preventive Intervention Perspective In this review of preventive interventions to pro- mote healthy families, we begin with an account of how sociology and psychology have helped shape conficting interpretations of changes in families over the past 70 years as evidence of either family decline or positive diversity. We argue that in either case, well-validated pro- grams are needed to strengthen families across the economic spectrum. Most parenting inter- ventions have been designed for, and attended by, mothers. We present an empirically based family risk and protection model to provide a rationale for interventions that also include fathers and focus on the coparenting relation- ship. Using an example of 7 clinical trials of a couples group intervention for parents from diverse economic and social backgrounds, we show that including fathers and addressing the coparental relationship as well as parenting contributes to healthier outcomes for mothers, fathers, and children. Finally, we discuss impli- cations for the future of family research and policy. Numerous changes in family structures and dynamics have occurred since the 1950s. In the United States and most Western industrial- ized nations, fewer people are getting married and more are cohabiting. Fewer women are Department of Psychology, University of California, Berke- ley, 140 Highland Boulevard, Kensington, CA 94708. E-mail: ccowan@berkeley.edu. Key Words: changing families, family policy, parenting inter- ventions, strengthening couple relationships. having babies, and increasing numbers of those who do are single parents. Fathers are increas- ingly absent (due to abandonment, separation, divorce, or incarceration). Increasing propor- tions of women who are mothers of young children are working outside the home. Gender stereotypic roles of men and women inside the home are changing. The income gap between families at the top and bottom is widening, and the cultural meaning and legal defnition of marriage is changing (the legal enshrinement of same-sex marriage being a prime example). Although the fact that these changes have occurred is not disputed, there have been remark- ably polarized interpretations of them within academic and policy circles. Just as these and other instances of family change have been inter- preted by some as alarming evidence that the institutions of marriage and family life are in a progressive decline, others have interpreted the same trends positively as signs of the emer- gence of “diverse forms and rich possibilities” for family life (Parke, 2013). The positions of researchers and policy makers on marriage and family life developments are refected in their proposals for what families need. Those who posit that marriage and family are in decline believe that the government ought to be involved in interventions that reverse, or at least halt, these changes by, for example, promoting traditional marriage or making it less costly for mothers of young children to stay at home. In contrast, pro- ponents of diversity and inclusion oppose these interventions, which they perceive as attempts to maintain the status quo even as social cir- cumstances and mores change, yet they advocate Family Relations (2019) 1 DOI:10.1111/fare.12359