Click to Play (streaming) and BBC iPlayer Desktop and Windows Media Player downloads offer subtitles, but subtitles are not available for mobiles or portable devices at present.
Streaming
If available, the Click to Play window will have the button (S) appear once you've started playing the programme (ie, after the BBC ident has played).
Click on to turn subtitles on or off.
Switching subtitles on Windows Media Player 10 or 11
You can also hold Ctrl+Shift+C on your keyboard to switch subtitles on and off.
For further help you can Contact Us, or you can discuss this issue at the BBC iPlayer messageboard.