This report investigates alternatives to the current targets related to early childhood education and care (ECEC), in particular by looking at socio-economic differences in the level of ECEC attendance in EU Member States. Using data from the EU Survey on income and living conditions (EU-SILC), it assesses different categorisations of socio-economic disadvantage, based on household income, maternal education and whether or not the child lives in a household which is at risk of poverty (AROP) or at risk of poverty or social exclusion (AROPE). Irrespective of which categorisation is used, the report shows considerably lower ECEC attendance rates for children from a lower socio-economic background when compared to those from a higher one. This suggests that the attempt to focus on particular subgroups of children is well justified. Based on a range of methodological and conceptual considerations, AROPE emerges as the most appropriate measure to build a possible ECEC indicator.