There is ongoing debate about the relative and absolute timing of formation of the Mount Isa copper and lead-zinc orebodies. This paper provides additional examples to support those illustrated in Perkins (1997,1998) and Perkins et al. (1998), which argued that these ore systems were cogenetic and formed late in the main deformation event which affected the mine environment (D3). This is done in terms of key questions which are often asked about the deposit, particularly in a regional context.