 From 1970 to 1973, he worked on an extensive research project with Douglas Yen in the Solomon Islands funded by a Captain James Cook Fellowship, after which he returned to Auckland for the remainder of his teaching career.He retired from teaching in 1992, at which time he was made Professor Emeritus.In addition to teaching at Auckland and Hawaii, Green periodically held active teaching and research positions at the American Museum of Natural History in New York, the Bernice P. Bishop Museum in Honolulu, and Te Whare Wānanga o Awanuiārangi in Whakatane, New Zealand.