2Plus New Zealand is a science-based business that offers sustainable and environmentally friendly water treatment products.
"It's for the right reasons. That's the key to my decision but equally I absolutely believe that CEOs shouldn't stay around too long. I believe there is a lifespan of five to eight years maximum and I am at that point now. It's unfair to the organisation to stay around too long."
Mr Coker said the decision to leave Priority One was difficult. "I love my team. I love my work and I love what we do," he said.
Mr Coker said he was proud of the growth of tertiary education in the region and the funding and support given to the House of Science.
Priority One board chairman Brett Hewlett said Mr Coker had a profound impact on the community.
"Today, Tauranga and the Western Bay of Plenty is the fastest growing regional economy and Priority One is acknowledged as one of the leading economic development agencies in the country," Mr Hewlett said.
"I wish to acknowledge the leadership, passion and dedication that Andrew has given to the role over the past 10 years."
Mr Coker would finish in August.
Priority One:
* Priority One is the Western Bay of Plenty region's economic development organisation, established in 2001 by the Tauranga and Western Bay of Plenty business community in partnership with the sub-region's local authorities. It was the first economic development organisation in New Zealand to be initiated by the business community and run along business principles of action and results.
www.priorityone.co.nz