Commissioned by Peter McLeavey on behalf of the Bank of New Zealand to be part of their new headquarters designed by Stephenson Turner for 1 Willis Street. In 1998 the building passed into the ownership of State Insurance, at which time, in consulation with Dawson, the sculpture was moved to its present location facing Willeston Street. The building has since been acquired by Precinct Properties New Zealand Ltd, and naming right acquired by Aon Insurance.

The form of 'Rock' is construct by a green-coated, metal grid. This is suspended on wires to emphasise the x-ray effect of the 'wire-frame' modelling. Both the shade of green and wire-frame may be references to computer aided design, a relatively new phenomenon in 1984.