Holding elections has become a global norm. Unfortunately, the integrity of elections varies strongly, ranging from “free and fair” elections with genuine contestation to “façade” elections marred by manipulation and fraud. Clearly, electoral integrity is a topic of increasing concern. Yet electoral integrity is notoriously difficult to measure, and hence taking stock of the available data is important. This article compares cross-national data sets measuring electoral integrity. The first part evaluates how the different data sets (a) conceptualize electoral integrity, (b) move from concepts to indicators, and (c) move from indicators to data. The second part analyses how different data sets code the same elections, seeking to explain the sources of disagreement about electoral integrity. The sample analysed comprises 746 elections in 95 third and fourth wave regimes from 1974 until 2009. I find that conceptual and measurement choices affect disagreement about election integrity, and also find that elections of lower integrity and post-conflict elections generate higher disagreement about election integrity. The article concludes with a discussion of results and suggestions for future research.