This paper examined the adoption of total quality management (TQM) by 228 New Zealand enterprises of all sizes, ranging from one employee to 8,800. Overall, 33% of firms in New Zealand used TQM, with an additional 5% of firms no longer using TQM. This indicates strong TQM adoption rates by current international standards. Factors tested to predict TQM adoption were organisational size, workplace autonomy, performance standards, use of teams and group problem solving. All these direct effects were supported. Further, the interacting effect of organisational size on these factors and TQM adoption was tested, with all effects significantly interacted by organisational size. When workplace autonomy, performance standards, use of teams and group problem solving factors were high for larger firms, they were all more likely to adopt TQM than larger firms with low values for these predictor factors. As a result, strong support was found for the interacting effect of organisational size. The implications for organisations and future research are discussed.