"Negative Numbers," In Our Time, BBC Radio 4, March 9, 2006.

  "A Countdown To Zero," 5 Numbers, BBC Radio 4, March 11, 2002.

  "As Simple As Pi," 5 Numbers, BBC Radio 4, March 12, 2002.

  "The Golden Rule," 5 Numbers, BBC Radio 4, March 13, 2002.

  "The Imaginary Number," 5 Numbers, BBC Radio 4, March 14, 2002.

  "Infinity," 5 Numbers, BBC Radio 4, March 15, 2002.

 "The Number Four," Another 5 Numbers, BBC Radio 4, October 27, 2003.

  "The Number Seven," Another 5 Numbers, BBC Radio 4, October 28, 2003.

  "The Largest Prime Number," Another 5 Numbers, BBC Radio 4, October 29, 2003.

  "Kepler's Conjecture," Another 5 Numbers, BBC Radio 4, October 30, 2003.

  "Game Theory," Another 5 Numbers, BBC Radio 4, October 31, 2003.

  "A Further Five Numbers," BBC Radio 4, August-September 2005.