American Nurses Credentialing Center (ANCC) is the world’s largest and most prestigious nurse credentialing organization, and is a subsidiary of the American Nurses Association (ANA). ANCC certification exams validate nurses’ skills, knowledge, and abilities and more than 80,000 advanced practice nurses are currently certified by ANCC. Before nurses can sit for a certification examination, they must demonstrate that they hold active RN licenses, have the appropriate education, and, for all but nurse practitioners and clinical nurse specialists, have experience in the specialty field. Those who have met the eligibility requirements can then register to take the certification examination. Each exam is designed by certified nurses in the specialty under the guidance of a professional psychometrician who ensures that all tests are psychometrically sound and legally defensible. Tests are based on the scope and standards of practice approved by the American Nurses Association Congress of Nursing Practice and Economics. The paper-and-pencil tests generally are given twice each year at many locations around the United States and at military installations abroad. Most Clinical Nurse Specialist and all Nurse Practitioner, Informatics Nursing, Cardiac/Vascular, and Gerontological examinations can be taken at the candidate’s convenience because they are computer-based.