Comparative effectiveness research (CER) represents an evolution in clinical decision-making research that allows for the study of heterogeneous groups of patients with complex diseases processes. It has foundations in decision science, reliability science, and health care policy research. Health care finance will increasingly rely on CER for guidance in the coming years. There is increasing awareness of the importance of decreasing unwarranted variation in health care delivery. In the past 7 years, Geisinger Health System has performed broad reengineering of its acute episodic and chronic care delivery models utilizing macrosystem-level application of CER principles. These provider-driven process initiatives have resulted in significant improvement across all segments of care delivery, improved patient outcomes, and notable cost containment. These programs have led to the creation of novel pricing models, and when “hardwired” throughout a care delivery system, they can lead to correct medical decision making by 100% of providers in all patient encounters. Neurosurgery as a specialty faces unique challenges and opportunities with respect to broad adoption and application of CER techniques.