Whitley industrial relations system, which was used in the civil service and local government. The system stemmed from work done by J. H. Whitley in 1916 and provided a framework for pay, terms and conditions. The NHS Whitley system had essentially been unaltered since its inception, although there had been some changes. Nevertheless, it had been heavily criticised for decades. These criticisms centred on its structure, complexity and over-centralisation, and its lack of flexibility. There was also concern that the existing pay scales were not easily adaptable to developing equal pay for work of equal value. In 1997 an eleven years long landmark legal case for equal pay in the NHS, Enderby v Frenchay Health Authority, decided that the pay of speech therapists, mostly women, was of equal value to higher paid clinical psychologists, mostly men. The differences in pay were because the two groups bargained separately under the Whitley system. This highlighted an important inadequacy of the NHS Whitley system. Negotiations on a new system began in February 1999, when the White Paper Agenda for Change was published. It aimed to address the issues of the Whitley system, and highlighted the need for a change of pay, career structures and terms and conditions of employment within the NHS. It stated that any new pay system must deliver equal pay for work of equal value. A number of organisations were involved in the discussions and negotiations including: The four health departments of England, Northern Ireland, Scotland and Wales NHS Employers - which represents NHS employers Twenty trade unions and representative bodies. Negotiations on the new pay system were concluded in November 2002, allowing full-scale testing of the new Agenda for Change pay system to begin at twelve "early implementer" sites in England in June 2003, with pilot sites in Scotland following. On 1 December 2004 it was implemented across the UK, with pay and conditions backdated to 1 October 2004. Although most NHS employees in England and Wales were quick to transfer to the new system with staff receiving their back-pay, Scotland had been slower to implement the system because Scotland took a more robust approach to the implementation. All the signatory organisations agreed to implement it through a partnership approach. In 2013 some amendments to Agenda for Change were agreed: incremental pay rises for staff will now be conditional on individuals meeting locally set performance requirements for the top