Geoff,
This really can't be done with a parameter, as the Init event (which gets the parameter) occurs after the DE is loaded.
You could try using a pre-defined variable (non-local) that is set before calling the form, and in the form's DE BeforeOpenTables, have code like:

THIS.Cursor1.CursorSource = cTableToUse

Mark

>I have a form that I pass a parameter into where the form uses different tables. For example, if the parameter is 'Order' I open the live transaction files and if it is 'Quote' I open the quote tables. I would combine the tables but due to the generation of order numbers I decided seperate tables would be better.
>
>I added the tables to the dataenvironment but where do you recommend me changing the alias? When the data environment loads it does not know the parameter passed into the form. However, if I don't specify an alias the grids and other controls do not know where to bind to....any suggestions?