“Migration” is a term used to describe the reformatting of materials or the moving of information from one format to a different format. The conversion of printed and original documents to microformats was a migration from paper, which was regarded as impermanent, to film, which was regarded as permanent. Today the term “migration” is most often used to denote the conversion of print or microform texts to electronic format to another. This paper begins with a brief history of the development of microforms as a storage and preservation medium with emphasis on the last two decades of the twentieth century in the United States. Recent issues in access and preservation are examined. Finally, the future of microforms is considered in light of migration to electronic formats for preservation.