[4][5] Anderson conducted a survey of archaeological sites in Tasman Bay for his Master of Arts degree in geography from the University of Canterbury, which he received in 1966.

[1] His thesis was on the subsistence behaviour at Black Rocks Peninsula in Palliser Bay, where he participated in a University of Otago archaeology research project from 1969 to 1972.

Important sites were excavated at Pūrākaunui, Lee Island in Lake Te Anau and the Shag River mouth.

As a result, Anderson examined the chronology of colonisation and re-dated moa hunting sites throughout New Zealand such as at Wairau Bar and Houhora.

In an interview about his 1998 book The Welcome of Strangers: an Ethnohistory of Southern Maori AD 1650–1850,[9] he described it as a book that "draws together the disparate sources of information about later southern Māori in an attempt to describe, in some detail, the origins and migrations of the historical peoples, their social and economic organisation, their distribution in the landscape and their responses to the arrival of European culture".

[10] In 2015, he collaborated with historians Judith Binney and Aroha Harris to publish Tangata Whenua: a history, which won an Ockham New Zealand Book Award in 2016.