Abstract: Methods, systems, and apparatus, including computer program products, are described for reconciling data. In one implementation, a method includes generating co-occurrence scores indicating whether data in entries in a first source of data co-occur within documents in a plurality of documents with data in entries in a second source of data. The co-occurrence scores for a given entry in the first source of data are used to identify a plurality of candidate matching entries in the second source of data for the given entry. Data in fields in the given entry are compared to that of one or more of the candidate matching entries to produce field similarity scores. The field similarity scores and the co-occurrence scores are used to determine a match for the given entry among the plurality of candidate matching entries.