Histology and anatomic pathology have historically been slow to accept many of the process changes that have been widely accepted in the clinical laboratory. In this article, we describe the application of the Toyota Production System (LEAN) to histology and anatomic pathology as implemented at the Avera McKennan Hospital laboratory. Avera McKennan is the flagship hospital of the Avera Health System, a faith based, not for profit healthcare system based in South Dakota. Comprised of 235 hospitals, clinics, and physicians, with over 12,000 employees, Avera Health is one of the largest healthcare systems in the region. Beginning in 2004, Avera McKennan's laboratory began its “LEAN journey” and in the intervening years has expanded it throughout all areas of the laboratory. Following the example set by the laboratory, many other areas of the hospital have joined in the LEAN Process Improvement journey. In January 2009, the Avera McKennan Laboratory became the first hospital laboratory in the US to achieve the CAP ISO-15189 accreditation in both clinical and anatomic pathology.