I have had an idea. How does this sound. I need to change the code but If i assign read only attributes of Medium Parcel to the items that need to go medium parcel this could be used to stop small parcel being used. This will work for single items or if any item in a package was marked with this attribute then the whole packet would be sent medium parcel. What it would not do is take in to account lots of small items making a parcel too big to send as medium parcel. It will take me a few weeks to sort this out but if this sound like a goer I'll give it a go! What do you think?