Quality by Design reflects the research and applied training conducted at Dartmouth Medical School under the leadership of Gene Nelson, Paul Batalden, and Marjorie Godfrey. The book includes the research results of high-performing clinical microsystems, illustrative case studies that highlight individual clinical programs, guiding principles that are easily applied, and tools, techniques, and methods that can be adapted by clinical practices and interdisciplinary clinical teams. The authors describe how to develop microsystems that can attain peak performance through active engagement of interdisciplinary teams in learning and applying improvement science and measurement; explore the essence of leadership for clinical Microsystems; show what mid-level leaders can do to enable peak performance at the front lines of care; outline the design and redesign of services and planning care to match patient needs with services offered; examine the issue of safety; describe the vital role of data in creating a rich and useful information environment; provide a core curriculum that can build microsystems’ capability, provide excellent care, promote a positive work environment, and contribute to the larger organization. Ancillary materials for use in classroom teaching, training, or coaching are available at https://clinicalmicrosystem.org/