I don't know whether there is a simpler way, but you could create a UDF, which returns a value. The group expression would invoke this UDF. For example:

Before running the report:

private Group_Field
do case
case ...
  Group_Field = "Field1"
...

In the report group expression:

GroupExp_Report1()

The UDF:

FUNCTION GroupExp_Report1
  return eval(Group_Field)
ENDFUNC

>Hi All,
>
>I was wondering if it is possible to create Dynamic Data Groupings in my report?
>
>I would like to store the field name into a Public Variable then use it as my Group Expression.
>
>

IIF(gnLevel1 == 1, &gcFieldGrp, "")

>
>gnLevel1 && Public Flag that indicates if the grouping should be applied.
> gcFieldGrp && Name of the field to base the grouping on.
>
> gcFieldGrp = IIF(Something, "Pers_No", "Proj_No")
>
>TIA
>Mike
>
>P.S. VFP6 SP5