In the eukaryotic nucleus, compaction of DNA into chromatin can limit the access of trans-acting factors, providing an additional level of regulation to processes such as transcription, replication, and repair. Recent studies have suggested that the protein products of the adenovirus 5 E1A oncogene can influence SWI-SNF and histone acetylase activities, two cellular processes that facilitate transcription in the context of chromatin. This review focuses on the unexpected effects of E1A on cellular processes that remodel chromatin in relation to its transcriptional and transforming activities.