William Grieve began his career in the early 1980s behind the camera, before moving into a production position at Larry Parr's company Mirage Films.

During his years at Mirage, Grieve worked in various roles as a production manager, associate producer, and location manager on feature films including Bruce Morrison car chase romp Shaker Run (1985) and Ian Mune's Bridge To Nowhere (1986). He was also involved on the New Zealand shoot for Roger Donaldson's American breakthrough No Way Out (1987).

In the early 1990s Grieve formed a television production company with director Bruce Morrison. Over the next ten years they worked together as the company Anson Grieve (later renamed Morrison Grieve) on many documentaries and series, including long-running hit Heartland.

Morrison won a best director award for the feature-length documentary The Road to Jerusalem, about poet James K Baxter. The film screened at the 1997 New Zealand Film Festival.

Grieve and Morrison have also worked extensively with New Zealand entertainer Gary McCormick. Their work together includes Bay Boys - a documentary in which McCormick returns to his former stamping ground of Titahi Bay - the 33-episode McCormick series, and Heartland. The latter show explored various New Zealand communities and personalities over four years, and won two awards at the New York Festival's International Film and Video Awards.

Other Grieve productions include Short Cuts - a weekly showcase of short films - the 1998 Frank Sargeson documentary Perfectly Frank, and 2001's Virginity, in which seven women are interviewed about their first sexual experiences. 

On the drama front, Grieve co-produced Staunch, a one-off drama about a young Māori woman complaining at unfair treatment by the police. Staunch was co-written by playwright Toa Fraser, and went on win multiple awards at the New Zealand Film and Television Awards.

Since the late 80s, Grieve has worked as a line producer for overseas filmmakers shooting in New Zealand. Working with his production service company Big Pictures, he has helped set up down under shoots on television commercials for advertisers in Europe, Asia and North America. He has also line produced special effects and stunt sequences for several international features and large format (IMAX) productions.

Sources include
big pictures website. Accessed 27 March 2011