Is there a way, using NHibernate (in C#), to retrieve the value of the primary key field for the record just inserted when calling an ISession's Save function? Thanks in advance for your help.

I assumed that you are using some form of auto-generated ID on the database table and you specified "native" or "identity" in the <generator> element in the mapping file. Given that my assumption is correct, when you save an entity using ISession.Save(), NHibernate puts the generated ID back into the ID property of your entity as defined in the <id> element in the mapping file.