When using BoundFIelds and domain objects... BoundFields use some algo that can't traverse the object hierarchy. What am I talking about? Take for instance a Northwind database, with certain objects mapped to data tables: public class Customer{ public int CustomerId; public IList<Order> Orders;} When binding to a list of Orders in a gridview: int customerId = int.Parse(selCustomer.Selec... customersList = CustomerService.GetCustomer... ......