In 1991 Cllr Rees gained a seat on Aberconwy Borough Council and held the office of Vice-Chairman of the Direct Services Organisation and Chairman of Planning. On Local Government Reorganisation in 1995, he was elected to serve on the new Unitary Conwy County Borough Council representing the Electoral Division of Llansanffraid Glan Conwy. He was the first Chair of Planning and Vice-Chair of the Tourism & Leisure Committee. In 1998 Cllr Rees was elected Vice-Chairman of the Council and after the May 1999 elections he was re-elected to Conwy CBC representing Llansanffraid Ward and took office as Chairman of the County Council.

He was a Cabinet Member from 1999 until 2004 holding the Portfolio with responsibility for Corporate Affairs and Communications. In 2003 he was delegated the task of assisting officers in organising the Golden Jubilee Festival of Youth at Eirias Park, Colwyn Bay in the presence of Her Majesty The Queen and HRH the Duke of Edinburgh and assisted her Majesty in the presentation ceremony.

He also chaired the Private Finance Initiative ( PFI ) Task Group which was responsible for gaining approval and funding of £42 million for the new build of Ysgol John Bright and the refurbishment of Ysgol Aberconwy and Ysgol Dyffryn Conwy, the largest education project ever undertaken in Wales.

From May 2004 to May 2006 he was Chairman of the Lifelong Learning Scrutiny Committee, and from 2006 until May 2008 he was Chairman of the Community Safety Scrutiny Committee.

On 1 May 2008, he was again re-elected to Conwy CBC for the Llansanffraid Ward and took on the post of Cabinet Member with the Performance and Modernisation Portfolio. This role gives him responsibility for Corporate Equalities & Diversity, Job Evaluation, I.C.T., E-Gov Strategy, Human Resources, PR and Corporate Image, Customer Service and Major Modernisation Projects. He is also the Chairman of the newly designated Public Confidence Committee.

Cllr Rees was elected to the North Wales Police Authority in May 2008.

Outside of the Council Cllr Rees is a Magistrate on the Conwy Bench, contested a Parliamentary Election for Clwyd West in 2001 and also contested the Conwy seat for the Welsh Assembly in 2003. He is also the Treasurer for the Glan Conwy Community Action Group, a local body who fund raise and carry out various events within the community. His recreational interests are travel, walking, reading and football. He is an Executive Member on the North Wales Coast Football Association.