James attended Wellington High School and then Victoria University of Wellington. He later lived in London for 12 years, during which time he worked for PriceWaterhouseCoopers and completed an MSc in sustainability and business leadership at the University of Bath.

In 2010, Shaw returned to NZ and worked as a consultant for HSBC bank on "environmental awareness programmes for future leaders". In 2014 was elected to the New Zealand parliament as a representative of the Green Party of Aotearoa New Zealand. He was elected the party's male co-leader in May 2015.

As well as being co-leader of the Green Party, Shaw is also the spokesperson for economic development, commerce, trade & investment, tourism, small business, sustainable business, SOEs, open government and electoral reform.