Assuming the authority conducted a procurement process, that the supplier you refer to is the successful bidder and as part of that procurement process a form of contract was issued by the authority, we would suggest that you check the procurement documents to determine whether the supplier proposing an alternative form of contract could result in exclusion. If this is the case (and assuming it was not explicitly stated that this would lead to exclusion), we would suggest responding to the successful bidder to ask for express confirmation that it accepts the form of contract issued by the authority as part of the procurement process (providing a deadline for this) or the authority will withdraw the award decision. If a procurement process was not undertaken (eg, the contract value is below threshold or an exemption applied) and your preference is to use the authority’s terms for the purchase, we would suggest that you ask the supplier to sign the authority’s form of contract which should include an express provision that this represents the entire agreement between the parties to the exclusion of any other terms.