This is largely an industrial area, where traditional heavy industries have been successfully replaced by manufacturing plants such as the giant Ford factory at Bridgend.
However, it also includes the holiday and retirement communities of the Porthcawl coastal area. It is well suited to further development, due to good transport links - principally, the M4.
Created in 1983, this was initially a Conservative seat. However, Win Griffiths has held the seat for Labour since 1987, steadily and consistently increasing his majority.
The Tory share of the vote fell by 13% at the last election. Mr Griffiths was rewarded with a post as a Welsh Office minister in 1997 but was sacked the following year.
Labour's dominance in the constituency showed clearly during the Assembly elections in 1999, but Carwyn Jones' majority was significantly smaller than those achieved for Westminster elections, following a surprisingly strong showing from Plaid Cymru, which despite coming third polled 19.7% of the vote.