Let me elaborate. The DDL is a list of domain values. The list is loaded from a domain table in my DB. The selected value of the list is supposed to reflect the value of of the PlantFamilyID field of each data record. Also, let me correct my earlier statement about what method of my control the GridView  invokes. I've observed that it automatically invokes the WebControl.Databind method of my DDL server control, first--not the CreateChildControls method. the the OnDataBinding method os invoked, then the CreateChildControls. These methods are all invoked automatically by virtue of the databinding context. I have no control over the sequence of events.

I've tried loading the list from the Load Event and I've had the same problems. When binding is occurring from the GridView, if I issue MyControl.Databind. I get the exception I mentioned in my original post. I can omit calling the databind method, but then If the control is not being bound to, the list doesn't get loaded. I'm still left with the same problem.

All comments are very much appreciated,

Andy