Mapping a collection that uses a private backing field

From Fluent NHibernate

This is part of the FAQs

If your entity uses a backing field for a property, or some other non-standard design, then you can map it using the Access property.

// model  
public class Account  
{  
  private IList<Customer> customers = new List<Customer>();  
 
  public IList<Customer> Customers  
  {  
    get { return customers; }  
  }  
}  
 
// mapping  
HasMany(x => x.Customers)  
  .Access.CamelCaseField();

The Access property can be used to set various combinations of Field and Property, with various casings and prefixes.

For example, for the same mapping but with the field called _customers you could use the Prefix.Underscore overload: Access.CamelCaseField(Prefix.Underscore).