Since 2000, Germany is experiencing an expansion of early childhood education and care (ECEC) institutions for children younger than three as well as increasing availability of full-day care for children aged three or older. More and more children attend ECEC centres for increasingly longer hours. Thus, ECEC centres are becoming an increasingly important environment for children and their parents. Given this background, an increasing number of economists are working on issues related to ECEC -with respect to either parental labour force participation or child outcomes. The K 2 ID-SOEP data sets are of particular interest to these researchers -and to all other social scientists investigating the impact of early childhood education and care across a variety of domains.The Socio-Economic-Panel Study (SOEP), as the largest and longest running multidisciplinary household panel in Germany (Wagner et al. 2007), started collecting information on ECEC centre attendance since its first wave in 1984. Irregularly, the SOEP collects information on the costs for ECEC care and the provider type. To learn more about the institutional context of ECEC, the aim of a larger research and data project funded by the Jacobs Foundation was to collect