Journal of Marriage and Family 65 (May 2003): 375–381 375 DEBORAH LOWE VANDELL University of Wisconsin—Madison KATHLEEN MCCARTNEY Harvard University* MARGARET TRESCH OWEN University of Texas at Dallas** CATHRYN BOOTH University of Washington*** ALISON CLARKE-STEWART University of California—Irvine****  Variations in Child Care by Grandparents During the First Three Years Routine child care by grandparents was examined for 1,229 children who were participants in the National Institute of Child Health and Human De- velopment (NICHD) Study of Early Child Care. Four groups were identified: extended full-time care, extended part-time care, sporadic care, and no routine care during the first three years. The odds of sporadic child care by grandparents were higher when mothers were relatively young and worked nonstandard hours. The odds of extended Department of Educational Psychology, 1025 West Johnson Street, University of Wisconsin, Madison, WI 53706 (dvandell@ facstaff.wisc.edu). *Harvard Graduate School of Education, 704 Larsen Hall, Appian Way, Harvard University, Cambridge, MA 02138. **School of Human Development, P.O. Box 830688, Mail Station GR4.1, University of Texas, Richardson, TX 75083- 0688. ***CHDD, 106 South Building, University of Washington, Seattle, WA 98195-7920. ****Psychology and Social Behavior, 3340 Social Ecology II, University of California, Irvine, CA 92697-7085. Key Words: child care, child-care selection, grandparents, maternal employment. full-time grandparent care versus extended part- time grandparent care were higher for mothers of color and mothers with more extensive full-time employment. All types of grandparent care were more likely when a grandparent lived in the household. These findings suggest that grandpar- ent care is heterogeneous and may occur in re- sponse to different family circumstances. In the United States, 63% of children under the age of 5 years receive nonmaternal child care on a routine basis (Smith, 2002). Researchers have typically focused on two types of child care: in centers and in child-care homes (cf. Lamb, 1998). Informal care settings have received much less at- tention, even though substantial numbers of chil- dren are cared for in these settings (Smith, 2002). In his comprehensive review of child-care re- search, Lamb (1998) called for an expanded re- search agenda that investigates informal arrange- ments. This research is needed because the development of policies to support working fam- ilies necessitates understanding which families use informal care and for what reasons (Kuhlthau & Mason, 1996; Presser, 1999). Additional research also is needed to identify meaningful variations in