The 1991 New Zealand Resource Management Act established an effects-based planning system intended to safeguard the biophysical resource base. The act and its subsequent practical implementation are deconstructed using an ecological modernisation framework. This demonstrates that many of the key policy instruments of the act can be accommodated within an ecological modernisation discourse. However, elements of discursive democracy introduced by the legislation have subsequently been impaired by technocorporatist legal formalism. This has prompted considerable debate about the perceived high process and compliance costs and the restricted public scrutiny of effects-based compliance in the new planning system. The reduced emphasis on socioeconomic effects within land-use development plans has impeded the promotion of sustainable spatial development strategies, frustrating attempts to deliver the ‘superindustrial ecological switchover’ sought by proponents of ecological modernisation. Recent legislation to extend the strategic powers of local government may help resolve this issue.