>But wouldn't the alltrim prevent that form happening?

Alltrims on fields in indexes don't do exactly what you think. If you apply an alltrim() to a field in an index expression, VFP trims it then pads it. It has done this since VFP 7 (maybe earlier, not sure). If you want the follwoing behavior:

"IDID2         "

then you need use the - operator in the key expression.

FIELD1-FIELD2

Field1 wll be trimmed with Field2 immediately following it.

Regards.