Thank you! That is interesting idea. Having rules in a spreadsheet would allow for much easier organization of rule definition. I could have rules that would require multiple steps (each step would be a row - with say 1st column specifying grouping). I could easily make them as complex as I want by adding data to a rule in as many columns as needed and interpreting that data based on header. I guess XML would be another way of defining rules but spreadsheet is more visual.