Yeah, I'm starting to get my head around this now.

So providing method/procedure names etc. are the same, it doesn't really matter what it's written in, as long as it retrieves/returns what is it expected of the data/front tier?

Kev

>One reference point is when you can swap one tier by a completly different one (maybe written in another language) and have the other tiers run untouched.
>
>>What I am sensing here is a very fine line between what is a tier, and what isn't.
>>
>>Where do you draw the line?