NHibernate

NHibernate is an open-source object-relational mapper (ORM) for the .NET framework, developed and maintained by an active community. Headquartered in the United States, NHibernate is a mature, feature-rich ORM that simplifies the mapping of .NET object models to relational databases, supporting a wide range of popular databases. With a growing community of seasoned developers, NHibernate is used in thousands of commercial and open-source projects.