Gambrill attended Samuel Marsden Collegiate School in Wellington, for her first few years of secondary schooling. She finished her high school studies at Nga Tawa Diocesan School in 1952. She studied law and was admitted as a solicitor in 1958 and as a barrister in 1960. In 1987 she was appointed as a master of the High Court of New Zealand, a position she held for 15 years.
Gambrill was appointed to the Insolvency Court in 1999, and she also served on the Legal Services Agency Review Panel. She retired from the judiciary in 2002.
Gambrill has held a number of community roles. She was the second president of the Auckland Zonta International Club, and has been an active member of the club for over 50 years. In the 1980s and 1990s she was the Chair of the Auckland Branch of the Samuel Marsden Collegiate Old Girls Association; she was the chairperson of the Auckland Decorative and Fine Arts Society and has served on the International Education Appeal Authority dealing with complaints from international students in New Zealand.
- "Engaged - Gisborne Photo News - No 68 : February 25, 1960". photonews.org.nz. Retrieved 2017-09-27.
- "Prominent Member History: Anne Gambrill - Zonta International District 16". Zonta International District 16. Retrieved 2017-09-27.
- "Samuel Marsden Collegiate School .::. Anne Gambrill". marsden.ultranet.school.nz. Retrieved 2017-09-27.
- "New Year Honours: The complete list". NZ Herald. 2003-06-01. ISSN 1170-0777. Retrieved 2017-09-27.