In Central and Eastern Europe following the political transformations of the late 1980s and early 1990s, there were dramatic declines in marriage and childbearing, significant increases in nonmarital cohabitation and childbearing, and a movement from reliance on abortion to a reliance on contraception for fertility limitation. Although many explanations have been offered for these trends, we offer new explanations based on ideational influences and the intersection of these ideational influences with structural factors. We focus on the political, economic, social, and cultural histories of the region, with particular emphasis on how countries in the region have interacted with and been influenced by Western European and North American countries. Our explanations emphasize the role of developmental models in guiding change in the region, suggesting that developmental idealism influenced family and demographic changes following the political transformations. Developmental idealism provides beliefs that modern family systems help to produce modern political and economic accomplishments, and it helps establish the importance of freedom and equality as human rights in both the public and private spheres. The disintegration of the governments and the fall of the iron curtain in the late 1980s and early 1990s brought new understanding about social, economic, and family circumstances in the West, increasing consumption aspirations and expectations which clashed with both old economic realities and the dramatic declines in economic circumstances. In addition, the dissolution of the former governments removed or weakened systems supporting the bearing and rearing of children; and the legitimacy of the former governments and their programs was largely destroyed, thereby removing government support for old norms and patterns of behavior. In addition, the attacks of previous decades on the religious institutions in the region had in many places left these institutions weak. During this period, many openly reached out to embrace the values, living standards, and economic, political, and familial systems of the West. And, the thirst for freedom–and its considerable expansion–operated in personal and familial as well as political and economic realms. These dramatic changes combined together to produce the many changes occurring in family and demographic behavior.