There were roughly 4 million children of undocumented parents in the United States in 2008. This article describes the effects that parental undocumented status can have on developmental contexts experienced in early childhood, before formal school entry. It focuses on early childhood as a crucial but still overlooked period for the study of children in immigrant families, a developmental stage when foundational cognitive and social skills are developing and in which social and economic disadvantage has particularly potent effects. Moreover, 91% of children under 6 with at least 1 undocumented parent are themselves U.S. citizens, which highlights the role of parental documentation status in affecting contexts of development that children may have access to but cannot select themselves. This article focuses on 3 sets of developmental contexts that may be sensitive to documentation status of parents: immediate postmigration contexts, in areas of legal, local enforcement policy, and neighborhood characteristics; everyday social settings, including program use, housing quality, and work conditions; and family processes.