Here's the scenario: Column A in the grid represents an IList of objects (the list is bound to an UltraCombo that is set as the EditorControl value of A). Just like A, column B contains an IList of different objects (initially populated as a superset of all possible objects for this column). The items in displayed in B's drop down list are dependent on the current value in A for the selected row. When the list in B is dropped down, I need to see a subset of items from the underlying IList (again, based on the value in A of the same row). What is the best way to handle this? (BTW, I am aware that the UltraDropDown is recommended over the UltraCombo when embedded in a grid.) Thanks.