The subcontract is intended for use in appointing a subcontractor where the contractor has been appointed under the NEC3 Engineering and construction options, the available secondary options, schedules of cost components and contract data. Construction Clients' Board endorsement of NEC3 The Construction Clients' Board (formerly Public Sector Clients' Forum) recommends that public sector organisations use the NEC3 contracts when procuring construction. Standardising use of this comprehensive suite of contracts should help to deliver efficiencies across the public sector and promote behaviours in line with the principles of Achieving Excellence in Construction.