I'm not sure why this wasn't implemented before the control was first released, or at least included in one of the many updates in the  years since. I'm also not sure why it has been a year and a half since this particular issue was brought to Telerik's attention and is still not implemented. Lastly, I'm not sure why such a feature requires customer feedback in order to implement. Its an obvious need which is already implemented in RadComboBox. For a control that serves very similar purpose as RadComboBox, one would think it would behave similarly. All of this just another example of why pretty much everything associated with RadDropdownList has delivered far less than expected, from its initial release which was lacking so many obvious needed features, to its continued status of being ignored for improvement by Telerik.