I have a list of P.O. Boxes and I need to detect and remove duplicates. Of course the column contains P.O. Boxes with all sorts of formats (ie. "po box," "p.o. Box," "Po Box," "P.O. Box," "P. O. Box," etc.). If I normalize all of them to the same format I will easily be able to remove the dups. I thought I'd first remove all periods in the column, then apply UPPER to get them all to uppercase. Then remove all spaces and look for dups. I would probably add a space back between the "O" and the following numbers.