A critical or clinical pathway defines the optimal care process, sequencing and timing of interventions by healthcare professionals for a particular diagnosis or procedure. It is a relatively new clinical process improvement tool that has been gaining popularity across hospitals and various healthcare organisations in many parts of the world. It is now slowly gaining momentum and popularity in Asia and Singapore. Clinical pathways are developed through collaborative efforts of clinicians, case managers, nurses, and other allied healthcare professionals with the aim of improving the quality of patient care, while minimising cost to the patient. Clinical pathways have been shown to reduce unnecessary variation in patient care, reduce delays in discharge through more efficient discharge planning, and improve the cost-effectiveness of clinical services. The approach and objectives of clinical pathways are consistent with those of total quality management (TQM) and continuous clinical quality improvement (CQI), and is essentially the application of these principles at the patient's bedside. However, despite the growing popularity of pathways, their impact on clinical outcomes and their clinical effectiveness remains largely untested and unproven through rigorous clinical trials. This paper begins with an overview of the nature of clinical pathways and the analysis of variances from the pathway, their benefits to the healthcare organisation, their application as a tool for CQI activities in direct relation to patient care, and their effectiveness in a variety of healthcare settings. The paper describes an evaluation of the impact of a clinical pathway on the quality of care for patients admitted for uncomplicated acute myocardial infarction (AMI) through an analysis of variances. The author carried out a one year evaluation of a clinical pathway on uncomplicated AMI in Changi General Hospital (CGH) to determine its effectiveness and impact on a defined set of outcomes. A before and after nonrandomized study of two groups of patients admitted to the Hospital for uncomplicated AMI was done. A total of 169 patients were managed on the clinical pathway compared to 100 patients in the control (historical comparison) group. Outcomes were compared between the two groups of patients. Restriction and matching of study subjects in both groups ensured that the patients selected were comparable in terms of severity of illness. The results showed that the patients on the clinical pathway and the comparison group were similar with respect to demographic variables, prevalence of risk factors and comorbidities. There was a statistically significant reduction in the average length of stay after implementation of the clinical pathway. This was achieved without any adverse effect on short term clinical outcomes such as in-hospital mortality, complication rate and morbidity. There were no significant difference in readmission rates at 6 months after discharge. The paper concludes that clinical pathways, implemented in the context of an acute care general hospital, is able to significantly improve care processes through better collaboration among healthcare professionals and improvements in work systems.