In this unit we see how the multilevel model provides a framework for combining individual level survey data with aggregate group level data. We illustrate this through an example where individual level data from the European Social Survey are combined with aggregate, country level data from the Eurostat New Cronos data that may be accessed via the UK Data Service. The dependent variable in our example is whether or not the individual turned out to vote in the most recent election in their country of residence. We restrict the analysis to those people who were of voting age at the most recent election in their country of residence.