This report is based on many years' experience undertaking biomonitoring programmes, both in New Zealand and in the United States. We especially thank Auckland Regional Council for financial and in-kind support for the development of a soft-bottomed MCI for the Auckland region. We thank Mike Thompson from the Ministry for the Environment for organising the Ministry contract that has enabled this report to be prepared, and for his helpful critique on the draft report. The Ministry for the Environment, Chris Fowles (Taranaki Regional Council), Brett Stansfield (Hawke's Bay Regional Council), Trevor James (Tasman District Council), and Kevin Collier (Environment Waikato) provided helpful comments on a draft of this report. Nevertheless, the views expressed in this report are those of the authors and are not necessarily endorsed by the various reviewers.