HA! I can actually do better... Try dealing with Utilities (gas, water, electricity).... across multiple states... each state has it's own interpretation as to what should be in the EDI files... and even in the same state, it can vary since 90% of the information is "optional" ... or the spec simply state "you have to have this" ... but doesn't say HOW to represent "this" ... so one utility will use "this" while another will use "ThIs" ... and a third will send "1" for this "2" for that and "3" for the other... glad it's not something I deal with any longer.

-tg