Methods and systems for extraction of transaction data for compliance monitoring, particularly useful in a system for monitoring electronic transactions of an enterprise and detecting exceptions indicating noncompliance with enterprise policies. Data extractors obtain data from various data sources and provide the data for use by a transaction analysis engine that executes computer-executable compliance policy statements against extracted data. Data extractors include one or more of following: a master extractor, a log extractor, a resync extractor, a programmatic extractor, an environmental source extractor, and an external source extractor. Data extraction is effected by using the master extractor and / or programmatic extractor to extract an initial subset of information about monitored transactions from an enterprise system, and then using the log extractor, the resync extractor, the programmatic extractor, the environmental source extractor, and / or the external source extractor to extract a second subset of information about changed data.