The basic technologies used in preanalytic processes for chemistry tests have been mature for a long time, and improvements in preanalytic processes have lagged behind improvements in analytic and postanalytic processes. We describe our successful efforts to improve chemistry test turnaround time from a central laboratory by improving preanalytic processes, using existing resources and the principles of lean production. Our goal is to report 80% of chemistry tests in less than 1 hour and to no longer recognize a distinction between expedited and routine testing. We used principles of lean production (the Toyota Production System) to redesign preanalytic processes. The redesigned preanalytic process has fewer steps and uses 1-piece flow to move blood samples through the accessioning, centrifugation, and aliquoting processes. Median preanalytic processing time was reduced from 29 to 19 minutes, and the laboratory met the goal of reporting 80% of chemistry results in less than 1 hour for 11 consecutive months.