>I have a Parent-Children-Grandchildren form which the user requries to copy records of. In the sense that he is adding a record and he knows the previously entered parent record identification details, for eg. OIO no.

>My question is what kind of a UI should be provided. Also the parent table has children and grandchilren tables, how to manage the stuff in a expandable manner, even if I hardcode the name I would want to have some flexibility in terms of table expansion. Fields will be added and removed as and when required so except for FK, PK and OIONo nothing is predictable.

In my opinion treeview ActiveX can solve your problem as you can display the parent – childs - childs in a proper way. You can add shortcut menu which can be displayed by right mouse click on any node for add/delete/move records. For other detail use PageFrame and each page can display the detail information for the specific level which can be bound with treeview.
I have added treeview in a form and the users can add records up to 5th level.