Evidence-based medicine is a tool of considerable value for medicine and neurosurgery that provides a secure base for clinical practice and practice improvement, but is not without inherent drawbacks, weaknesses and limitations. EBM finds answers to only those questions open to its techniques, and the best available evidence can be a far cry from scientific truth. With the support and backing of governmental agencies, professional medical societies, the AAMC, the ACGME, and the ABMS, EBM is likely here to stay. The fact that: (1) EBM philosophy and critical appraisal techniques have become fully integrated into the training and culture of our younger colleagues, (2) that maintenance of certification will require individuals to demonstrate personal evidence based practice based on tracking and critical analysis of personal practice outcomes as part of the performance-based learning and improvement competency, and (3) that the progressively growing national healthcare expenditures will necessitate increasing basis of reimbursement and funding based on evidence-based effectiveness and guidelines, all point to the likelihood that complete immersion of neurosurgical practice in EBM is inevitable. This article thoroughly explores the history of EBM in medicine in general and in neurosurgery in particular. Emphasis is placed on identifying the legislative and regulatory motive forces at work behind its promulgation and the role that organized medicine has taken to facilitate and foster its acceptance and implementation. An accounting of resources open to neurosurgeons, and a detailed description EBM clinical decision-making methodology is presented. Special emphasis is placed on outlining the methodology as well as the limitations of meta-analyses, randomized clinic trials, and clinical practice parameter guidelines. Commonly perceived objections, as well as substantive problems and limitations of EBM assumptions, tools, and approaches both for individual clinical practice and health policy design and implementation are explored in detail.