Jason,

Thanks for the reply. I failed to mention in my original post that i have implemented the ISupportIntialize of the usercontrol UC2, in which on the EndInit I am setting the BindingSource of the mmUltraCombo. This still does not seem to work.

However, after reading your post and reading the section you recommended "Programaticlly Data Binding User Interface Controls", because I am using the UltraCombo, I do not have access to BindingSourceMember, whereas I do have access to BindingSourceValueMember and BindingSourceDisplayMember which I have both set in the EndInit. Even with all of these set, it still does not seem to be binding.

Should I be setting these "NOthing" so that the registration is triggered?

Would calling the RegisterBoundControl method help as well?

Thanks again...

Scott