Following its publication in December 2010 of the fair payment principles to be followed by all central government construction clients, the Cabinet Office has now published Fair Payment Information Note 1/2011. This contains a “Z clause” that deals specifically with the principle of fair payment and is to be inserted into the NEC Engineering and Construction Contract (ECC). As readers may already know, Option Z of the ECC allows the parties to incorporate bespoke provisions into the contract and such provisions are commonly referred to as “Z clauses”. The new “Z clause” requires a contractor to pay its sub-contractors within 19 days of payment becoming due under the main contract and without reference to the amount certified to the contractor under the main contract.