Carmen,

Create a new table named TransType.dbf;

TransCode N(the same width as the code in the AR table)
TransDesc C(80)

In this table put records like these;

TransCode TransDesc
1         Invoice
2         Adjustment
8         Cash Receipt
etc...

Now in the DE of the form set up the ARTable to be related into the TransType table on the Code and in teh Grid make the Conrtolsource for the column;

TransType.TransDesc