The Professional Services Contract is intended for use in the appointment of a supplier to provide professional services. It can be used for appointing project managers, supervisors, designers, consultants or other suppliers under NEC contracts and can also be used for appointing suppliers on non-NEC construction projects or for non-construction projects. This document contains the core clauses, the relevant main option clauses, the secondary option clauses and the contract data. The Guidance Notes explain the structure of the Professional Services Contract and the reasons for its provisions. They explain the "shell" of the contract and the need to provide important additional information such as the scope. The main options, dispute resolution options and the secondary options are all explained together with the basis of appointing a consultant. Explanatory notes on individual clauses and worked examples of contract data are also provided. The Flow Charts clearly set out the procedural logic of the 28 clauses. 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.