New Post: Getting Item ID Before Document Saved.

Thanks. presaving the form then using the edit form sounds like a good approach, as then I'll only have one form to customise as well. It should be fine as regards to cancelling etc, as the order form has various statuses and won't actually be submited, until they choose to submit it, regardless of save. If they never actually submit it, it'll just sit there as draft and could be cleaned up later.

I'd like to just use the standard list "New" button. Is it possible to override that button, or would I have to update newform, to create the order, then redirect to the edit form from there?

The post processing technique using the source URL is interesting. I'll try the other way 1st I think, but sure that will come in handy at some point.

What part don't you understand about the relationship? It's similar to "add to basket" functionality on websites. I'm always open to suggestions if there's a better way, but not sure how you mean about standard list functionality.

I have an online order from effectively, from which people can order 100's products per order. Instead of having 100's of fields in the order form, products when added are created in another list, with the order id stored and displayed in the order. So the order actually consists of all products ordered with that order ID.