well thanks for the response.
i am dragging a string from treeview into the textbox which already contains some text.
i can get the mouse position w.r.t. the text box by
Point pt = m_textBox.PointToClient(new Point(theDragEventArgs.X, theDragEventArgs.Y));
i am not able to proceed from that.
all my tries became futile.
Regards.
sethuramanV