In the clinical management of infertility one purpose of the diagnostic process is to document the occurrence, timing, and quality of ovulation. Thus, there are diagnostic tests for ovulation detection, tests for the prediction of ovulation, and other tests that evaluate the quality of the luteal response. The further investigation of the woman who does not ovulate, and the evaluation of ovulatory dysfunction associated with hyperprolactinemia, hypothalamic disorders, and the polycystic ovarian syndrome represent diagnostic activities that, although related, are beyond the scope of this article.