The ACNM Certification Council is responsible to the American College of Nurse-Midwives for the development, administration, and evaluation of a psychometrically sound and legally defensible certification examination in nurse-midwifery. A task analysis study was conducted to investigate the knowledge, skills, and abilities that define American nurse-midwifery practice. A stratified sample of 825 American College of Nurse-Midwives members was asked to rate the frequency of performance and the criticality of 189 nurse-midwifery activities and 109 discrete diagnoses that the nurse-midwife might encounter while providing clinical care. The frequency and criticality ratings were combined to generate an importance weight for each activity. Study data will be used as the basis of the examination blueprint in order to ensure job-related content validity. Aggregate data can also be used for curriculum development, self-assessment, and evaluation research purposes.