Roger Hugh Williams, CBE (born 22 January 1948) is a Welsh Liberal Democrat politician who was the Member of Parliament (MP) for Brecon and Radnorshire from 2001 to 2015.

At the 1999 Welsh Assembly election Williams contested Carmarthen West and South Pembrokeshire but finished a distant fifth.

[1] In 2001, he was elected to represent the constituency of Brecon & Radnorshire, subsequently holding the seat with a majority of 751 following the retirement of fellow Liberal Democrat Richard Livsey.

He served as Shadow Welsh Secretary in the Liberal Democrat Frontbench Team in the 2005-10 Parliament and was re-elected at the 2010 election with a majority of 3,747.

Williams was appointed Commander of the Order of the British Empire (CBE) in the 2013 New Years Honours List for public and political service.