The first goal of this investigation was to undertake a non-equivalent quasi-experimental design to test the effect of a total Quality management (TQM) approach to improve the appropriateness of clinical laboratory test utilisation in the management of early acute myocardial infarction (AMI). The study was conducted at 2 public hospitals in Sydney over a 30 month period, and in 2 stages- pre and post TQM intervention. Using specifically a Continuous Quality Improvement (CQI) FOCUS-PDCA model, a multidisciplinary team was empowered to make appropriate changes in order to improve a variety of problem areas that affected the total pathology service. Improvement was directed at the total system of pathology testing, not just test ordering. It was observed that the introduction of a TQM environment had provided a more committed, integrated and motivated clinical care effort towards improving the appropriateness of test ordering. Such team efforts were accompanied by demonstrated customer satisfaction at various aspects of the laboratory service and further benefits to patient care. Patient care benefited greatly from the highly significant changes towards more appropriate timing of blood collections for cardiac enzyme testing. Other improvements included overall improvements to the turnaround time of test results, reductions in specimen delivery delays, more appropriate use of clinical laboratory tests, a streamlined distribution of printed reports and marked improvements in communication between staff involved in the process of test ordering. Of major importance was the finding that CQI strategies resulted in substantial savings of 23.0% of the overall cost of pathology services. Adoption of the TQM approach appears to be a strategy worthy of exploration by laboratory directors and health administrators interested in improving patient care while at the same time reducing expenditure. / Doctor of Philosophy (PhD)