Nearly, 2 million children in the United States live in military families. Throughout all branches of the U.S. military since September 11, 2001, ca 700,000 children have had or currently have a parent deployed to the combat zones of Iraq or Afghanistan. As a result, researchers are paying increasing attention to the effects of military deployment on children and families. These facts and the changing landscape of military service point to the need to empirically examine the impact of parental military deployment on immediate and longer term child adjustment. The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) recently initiated a research program to address these issues. This article draws on attachment and family stress theories as a frame for discussing the effects of parental deployment on child adjustment and family functioning and for outlining the NICHD research priorities. It discusses areas where developmental science can make important contributions as well as challenges for conducting research in military families.