James David Campbell Walker (born 25 August 1968) is a British former Olympic oarsman and subsequently climate change campaigner from Chester.

[2] He was a world junior silver medalist in 1986, competing in a British four with Matt Brittin, Jonny Searle and Mark Pierce.

As part of the debate following the Atlanta Olympics about the then chronic lack of funding for elite sport in Britain,[6] Walker was identified by the Guardian newspaper as one of five examples of unfunded Team GB athletes deserving of National Lottery support for the 1996-2000 Olympic cycle, alongside sailor Sir Ben Ainslie, swimmer Paul Palmer, sprinter Angie Thorp and canoeist Lynn Simpson.

[12] From 2007 to 2017 he was a final jury member for the annual Dutch Postcode Lottery Green Challenge, one of the world’s biggest sustainability competitions by prize value.

[13] Until 2023 he led partnerships and fundraising efforts for the United Nations-affiliated initiative SEforALL, reporting to two successive Special Representatives of the UN Secretary-General.